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Hydroplane

Hydroplane

:This article is about the hydroplane, a specific type of motorboat used in sport of hydroplane racing. See hydroplaning for other uses. hydroplaning A hydroplane (or hydro, or thunderboat) is a very specific type of motorboat used exclusively for racing. One of the unique things about these boats is that they only use the water they're on for propulsion and steering (not for floatation)--when going full speed they are primarily held aloft by a principle of aerodynamics known as "planing", with only a tiny fraction of their hull actually touching the water.

Hydroplane design

hull The basic principle of the hull design of most hydroplanes has remained much the same since the 1950s: two sponsons in front, one on either side of the bow; behind the wide bow, is a narrower, mostly rectangular section housing the driver, engine, and steering equipment. The aft part of the vessel is supported, in the water, by the lower half of the propeller, which is designed to operate like that. The goal is to keep as little of the boat as possible from touching the water, since water gives more drag than air. One of the few significant attempts at a radically different design since the three-point propriding design was introduced was referred to as Canard. It reversed the width properties, having a very narrow bow that only touched the water in one place, and two small outrigger sponsons in the back. outrigger Early hydroplanes had mostly straight lines and flat surfaces aside from the uniformly curved bow and sponsons. The curved bow was eventually replaced by what is known as a pickle fork bow, where a space is left between the front few feet of the sponsons. Also, the centered single, vertical tail (similar to the ones on most modern airplanes) was gradually replaced by a horizontal stabilizer supported by vertical tails on either side of the boat. Later, as fine-tuning the aerodynamics became more important, the bottoms of the main hull have subtle curves to give the best lift.

Unlimited hydroplane engines

The aerodynamics industry has been the main source of engines for the boats. For the first few decades after World War II, they used surplus World War II-era internal-combustion airplane engines. The manufacturers of the two most commonly used engines are Rolls Royce and their Allison division. The loud roar of these engines earned hydroplanes the nickname thunderboats. Donald Campbell attempted world speed records in a jet engine powered hydroplane, Bluebird in the early 1950s. The Ted Jones-designed Slo-Mo-Shun IV three-point, Allison-powered hydro set the water speed record (160.323 mph) in Lake Washington, off of Seattle (USA)'s Sand Point, on June 26, 1950, breaking the previous (10+ year-old) record (141.740 mph) by almost 20 mph. Starting in 1980, they have increasingly used Vietnam War-era turbine engines from helicopters (actually, in 1973-1974, one hydroplane, the U-95, used turbine engines in races to test the technology). The manufacturer of the most commonly used turbines is Lycoming. Efforts have occasionally been made to use automotive engines, but they generally haven't been proven to be competitive. automotive

External links


- -- Hydroplane
- [http://www.thunderboats.org/restorations.shtml Nice set of pictures showing bow design evolution, from the Hydroplane and Raceboat Museum] Also note the wood grain visible on some of the early boats--later hydros have used fiberglass and assorted hi-tech materials
- [http://www.hydroplane-racing.com Hydroplane-Racing.com] : A community site for Hydroplane Racing fans young and old!
- [http://www.abrahydroplanes.com/ The American Boat Racing Association's hydroplane website] Category:Boat types Category:Motorboat racing

Hydroplaning

Hydroplaning and hydroplane have several meanings:
- With boats, planing or hydroplaning is a method by which a hull skims over the surface of the water, rather than plowing through it.
- With rubber wheeled vehicles, aquaplaning, planing or hydroplaning is a cause of loss of steering control when a layer of water prevents direct contact between the tires and the road surface.
- Hydroplane often refers to a specific type of fast motorized boat.
- Hydroplane sometimes refers to any watercraft that is specially designed to plane, for example a hydrofoil.
- Hydroplane sometimes refers to a seaplane, an aircraft that can land on water.
- Hydroplane is also a technical term for a submarine wing used to help control depth, analogous to the elevators on the tail of an aircraft. The above terms can vary in meaning, particularly comparing usage in the US and in Europe.

Motorboat

A motorboat generally speaking is a vessel other than a sailboat or personal watercraft, propelled by an internal combustion engine driving a jet or a propeller. A speedboat is a small motorboat designed to move quickly, used in races, for pulling water skiers, as patrol boats, and as fast-moving armed attack vessels by the military. There are three popular variations of powerplants: inboard, inboard/outboard, and outboard. If the engine is installed within the boat, it's called a powerplant; if it's a removable module attached to the boat, it's commonly known as an outboard motor. An outboard motor is installed on the rear of a boat and contains the internal combustion engine, the gear reduction, and the propeller. An inboard/outboard contains a hybrid of a powerplant and an outboard, where the internal combustion engine is contained inboard and the gear reduction and propeller are outside. A purely inboard boat contains everything except a shaft and a propeller inside the vessel. There are two configurations of an inboard, v-drive and direct drive. A direct drive has the powerplant mounted near the middle of the boat with the propeller shaft straight out the back, where a v-drive has the powerplant mounted in the back of the boat facing backwards having the shaft go towards the front of the boat than making a 'V' towards the rear. Motorboats vary greatly in size and configuration, from the 4-meter, open Boston Whaler type to the luxury mega-yachts capable of crossing an ocean.

History

Although the Screw propellor had been added to an engine (steam engine) as early as the 18th century in Birmingham, England by James Watt, the petrol engine only came about in the later part of the 20th century, at which point Frederick William Lanchester recognised the potential of combining the two components to create the first all British powerboat, tested in Oxford England the powerboat was born. Category:Boat types ja:モーターボート

Steering

Steering is the term applied to the collection of components, linkages, etc. which allow for a car or other vehicle to follow a course determined by its driver, except in the case of rail transport in which rail tracks combined together with railroad switches provide the steering function. railroad switch

Introduction

The most conventional steering arrangement is to turn the front wheels using a hand–operated steering wheel which is positioned in front of the driver, via the steering column, which may contain universal joints to allow it to deviate somewhat from a straight line. Other arrangements are sometimes found on different types of vehicles, for example, a tiller or rear–wheel steering. Tracked vehicles such as tanks usually employ differential steering—that is, the tracks are made to move at different speeds or even in opposite directions to bring about a change of course.

Rack and pinion, recirculating ball, worm and sector

Tracked vehicle Many modern cars use rack and pinion steering mechanisms, where the steering wheel turns the pinion gear; the pinion moves the rack, which is a sort of linear gear which meshes with the pinion, from side to side. This motion applies steering torque to the kingpins of the steered wheels via tie rods and a short lever arm called the steering arm. Older designs often use the recirculating ball mechanism, which is still found on trucks and utility vehicles. This is a variation on the older worm and sector design; the steering column turns a large screw (the "worm gear") which meshes with a sector of a gear, causing it to rotate about its axis as the worm gear is turned; an arm attached to the axis of the sector moves the pitman arm, which is connected to the steering linkage and thus steers the wheels. The recirculating ball version of this apparatus reduces the considerable friction by placing large ball bearings between the teeth of the worm and those of the screw; at either end of the apparatus the balls exit from between the two pieces into a channel internal to the box which connects them with the other end of the apparatus, thus they are "recirculated". The rack and pinion design has the advantages of a large degree of feedback and direct steering "feel"; it also does not normally have any backlash, or slack. A disadvantage is that it is not adjustable, so that when it does wear and develop lash, the only cure is replacement. The recirculating ball mechanism has the advantage of a much greater mechanical advantage, so that it was found on larger, heavier vehicles while the rack and pinion was originally limited to smaller and lighter ones; due to the almost universal adoption of power steering, however, this is no longer an important advantage, leading to the increasing use of rack and pinion on newer cars. The recirculating ball design also has a perceptible lash, or "dead spot" on center, where a minute turn of the steering wheel in either direction does not move the steering apparatus; this is easily adjustable via a screw on the end of the steering box to account for wear, but it cannot be entirely eliminated or the mechanism begins to wear very rapidly. This design is still in use in trucks and other large vehicles, where rapidity of steering and direct feel are less important than robustness, maintainability, and mechanical advantage. The much smaller degree of feedback with this design can also sometimes be an advantage; drivers of vehicles with rack and pinion steering can have their thumbs broken when a front wheel hits a bump, causing the steering wheel to kick to one side suddenly (leading to driving instructors telling students to keep their thumbs on the front of the steering wheel, rather than wrapping around the inside of the rim). This effect is even stronger with a heavy vehicle like a truck; recirculating ball steering prevents this degree of feedback, just as it prevents desirable feedback under normal circumstances. The steering linkage connecting the steering box and the wheels usually conforms to a variation of Ackermann steering geometry, to account for the fact that in a turn, the inner wheel is actually traveling a path of smaller radius than the outer wheel, so that the degree of toe suitable for driving in a straight path is not suitable for turns.

Four wheel steering

The system

4 wheel steering (or all wheel steering) is a system employed by some vehicles to increase vehicle stability while maneuvering at high speed, or to decrease turning radius at low speed. In most 4-wheel steering systems, the rear wheels are steered by a computer and actuators. The rear wheels generally cannot turn as far as the front wheels. Sports cars sometimes include 4-wheel steering for stability at high speeds. When performing an abrupt lane change at highway speeds, for example, a car with 4-wheel steering will avoid rear suspension loading common in 2-wheel steering cars. Because the rear wheels steer in the same direction as the front wheels, the car is transitioned more gently into turning. Alternatively, several systems (including Delphi's Quadrasteer, and the system in Honda's Prelude line) allow for the rear wheels to be steered in the opposite direction as the front wheels during low speeds. This allows the vehicle to turn in a significantly smaller radius—sometimes critical for large trucks or vehicles with trailers.

Recent application

Recently, four wheel steering has been offered in trucks with four wheel drive used for towing. All four wheels turn at the same time when you steer. There are controls to switch off the rear steer and options to steer only the rear wheel independent of the front wheels. At slow speeds (e.g. parking)the rear wheels turn opposite of the front wheels, reducing the turning radius by up to twenty-five percent, while at higher speeds both front and rear wheels turn alike (electronically controlled), so that the vehicle may change direction with less yaw, enhancing straight-line stability. The "Snaking effect" experienced during motorway drives while towing a caravan is thus largely nullified. Four wheel steering is popular in large farm vehicles and trucks. General Motors offers Delphi's Quadrasteer in their consumer Silverado/Sierra and Suburban/Yukon. However, only 16,500 vehicles have been sold with this system since its introduction in 2002 through 2004. Due to this low demand, GM will not offer the technology on the 2007 update to these vehicles. Previously, Honda had four wheel steering as an option in their 1988-1994 Prelude, and Mazda also offered four wheel steering on the 626 in 1988. Neither system was very popular, in that whatever improvement they brought to these already excellent-handling vehicles was offset by an unavoidable decrease in sensitivity caused by the increased weight and complexity. Some vehicles now offer a form of "passive" four wheel steering, where the bushings by which the rear suspension attaches to the automobile are designed to compress in a precise direction under the forces of steering, thus slightly altering the rear suspension geometry in such a manner as to enhance stability.

Cars with four wheel steering


- GMC Sierra (2002)
- Honda Prelude (1988)
- Mazda 626 (1988)
- Mitsubishi GTO (also sold as the Mitsubishi 3000GT and the Dodge Stealth)
- Nissan 240SX (SE-R models; available as an option)
- Nissan 300ZX (all Twin-Turbo Z32 models)
- Nissan Silvia (option on all S13 models)
- Nissan Skyline GT-R
- Toyota Aristo (1997)
- Toyota Celica (Option on 5th and 6th generation, 1990-1995)

Articulated steering

Toyota Celica Articulated steering is a system by which a four wheel drive vehicle is split into front and rear halves which are connected by a vertical hinge. The front and rear halves are connected with one or more hydraulic cylinders that change the angle between the halves, including the front and rear axles and wheels, thus steering the vehicle. This system does not use steering arms, king pins, tie rods, etc. as does four wheel steering. If the vertical hinge is placed equidistant between the two axles, it also eliminates the need for a central differential, as both front and rear axles will follow the same path, and thus rotate at the same speed.

Power Steering

Power steering aims to make steering less strenuous for the driver. There are two types of power steering systems--hydraulic and electric/electronic. There is also a hydraulic-electric hybrid system possible.

Safety

For safety reasons all modern cars feature a collapsible steering column which will collapse in the event of a heavy frontal impact to avoid excessive injuries to the driver. This safety feature first appeared on cars built by General Motors after an extensive and very public lobbying campaign enacted by Ralph Nader.

Cycles

Steering is crucial to the stability of bicycles and motorcycles (see article on bicycle).

Railroad vehicles

Railroad wheels have fixed axles and tyres with a greater inner than outer radius. Any movement off center automatically corrects itself because the wheel resting on a greater radius travels faster. This effect also allows for cornering. Wheels also have flanges to prevent derailing.

See also


- Steering wheel cover
- Caster angle
- Camber angle ----

External links


- [http://auto.howstuffworks.com/steering.htm How Car Steering Works (HowStuffWorks.com)] Category:Automotive steering technologies ja:ステアリング

Aerodynamics

Aerodynamics is a branch of fluid dynamics concerned with the study of gas flows, first analysed by George Cayley in the 1800s. The solution of an aerodynamic problem normally involves calculating for various properties of the flow, such as velocity, pressure, density, and temperature, as a function of space and time. Understanding the flow pattern makes it possible to calculate or approximate the forces and moments acting on bodies in the flow. This mathematical analysis and empirical approximation form the scientific basis for heavier-than-air flight. Aerodynamic problems can be classified in a number of ways. The flow environment defines the first classification criterion. External aerodynamics is the study of flow around solid objects of various shapes. Evaluating the lift and drag on an airplane, the shock waves that form in front of the nose of a rocket or the flow of air over a hard drive head are examples of external aerodynamics. Internal aerodynamics is the study of flow through passages in solid objects. For instance, internal aerodynamics encompasses the study of the airflow through a jet engine or through an air conditioning pipe. The ratio of the problem's characteristic flow speed to the speed of sound comprises a second classification of aerodynamic problems. A problem is called subsonic if all the speeds in the problem are less than the speed of sound, transonic if speeds both below and above the speed of sound are present (normally when the characteristic speed is approximately the speed of sound), supersonic when the characteristic flow speed is greater than the speed of sound, and hypersonic when the flow speed is much greater than the speed of sound. Aerodynamicists disagree over the precise definition of hypersonic flow; minimum Mach numbers for hypersonic flow range from 3 to 12. Most aerodynamicists use numbers between 5 and 8. The influence of viscosity in the flow dictates a third classification. Some problems involve only negligible viscous effects on the solution, in which case viscosity can be considered to be nonexistent. The approximations to these problems are called inviscid flows. Flows for which viscosity cannot be neglected are called viscous flows.

Aerodynamic forces on aircraft

viscous flow One of the major goals of aerodynamics is to predict the aerodynamic forces on aircraft. The four basic forces that act on a powered aircraft are lift, weight (or gravity), thrust, and drag. Weight is the force due to gravity and thrust is the force generated by the engine. Lift and drag are forces due to the motion of the vehicle through the air. Lift is defined as the aerodynamic force acting perpendicular to the relative airflow and drag is defined as the aerodynamic force acting parallel to the relative airflow. Lift is positive upwards and drag is positive rearwards.

Aerodynamics in other fields

Aerodynamics is important in a number of applications other than aerospace engineering. It is a significant factor in any type of vehicle design, including automobiles. It is important in the prediction of forces and moments in sailing. It is used in the design of small components such as hard drive heads. Civil engineers also use aerodynamics, and particularly aeroelasticity, to calculate wind loads in the design of large buildings and bridges.

Continuity assumption

Gases are composed of molecules which collide with one another and solid objects. In aerodynamics, however, gases are considered to have continuous quantities. That is, properties such as density, pressure, temperature, and velocity are taken to be well-defined at infinitely small points, and are assumed to vary continuously from one point to another. The discrete, molecular nature of a gas is ignored. The continuity assumption becomes less valid as a gas becomes more rarefied. In these cases, statistical mechanics is a more valid method of solving the problem than aerodynamics.

Conservation laws

Aerodynamic problems are solved using the conservation laws, or equations derived from the conservation laws. In aerodynamics, three conservation laws are used:
- Conservation of mass: Matter is not created or destroyed. If a certain mass of fluid enters a volume, it must either exit the volume or increase the mass inside the volume.
- Conservation of momentum: Also called Newton's second law of motion
- Conservation of energy: Although it can be converted from one form to another, the total energy in a given system remains constant. All aerodynamic problems are therefore solved by the same set of equations. However, they differ by the assumptions made in each problem. The equations become simpler as assumptions are made. Note that these laws are based on Newtonian Mechanics. They are not applicable in relativistic mechanics, which takes into account Einstein's theory of relativity. all the problem related to energy conservation must be well known

Subsonic aerodynamics

In a subsonic aerodynamic problem, all of the flow speeds are less than the speed of sound. This class of problems encompasses nearly all internal aerodynamic problems, as well as external aerodynamics for most aircraft, model aircraft, and automobiles. In solving a subsonic problem, one decision to be made by the aerodynamicist is whether or not to incorporate the effects of compressibility. Compressibility is a description of the amount of change of density in the problem. When the effects of compressibility on the solution are small, the aerodynamicist may choose to assume that density is constant. The problem is then an incompressible problem. When the density is allowed to vary, the problem is called a compressible problem. In air, compressibility effects can be ignored when the Mach number in the flow does not exceed 0.3. Above 0.3, the problem should be solved using compressible aerodynamics.

Transonic aerodynamics

Transonic aerodynamic problems are defined as problems in which both supersonic and subsonic flow exist. Normally the term is reserved for problems in which the characteristic Mach number is very close to one. Transonic flows are characterized by shock waves and expansion waves. A shock wave or expansion wave is a region of very large changes in the flow properties. In fact, the properties change so quickly they are nearly discontinuous across the waves. Transonic problems are arguably the most difficult to solve. Flows behave very differently at subsonic and supersonic speeds, therefore a problem involving both types is more complex than one in which the flow is either purely subsonic or purely supersonic. Š

Supersonic aerodynamics

Supersonic aerodynamic problems are those involving flow speeds greater than the speed of sound. Calculating the lift on the Concorde during cruise can be an example of a supersonic aerodynamic problem. Supersonic flow behaves very differently from subsonic flow. The speed of sound can be considered the fastest speed that "information" can travel in the flow. Gas travelling at subsonic speed diverts around a body before striking it, so it can be said to "know" that the body is there. Air cannot divert around a body when it is travelling at supersonic speeds. It subsonic flow and a diffuser in supersonic flow). Subsonic flow additional shock waves. In this case the fuselage reuses some displacement of the wings.

See also


- List of aerospace engineering topics
- List of engineering topics
- Automotive_aerodynamics
- Aeronautics
- Fluid dynamics
- Nose cone design
- Bernoulli's equation
- Navier-Stokes equations
- Center of pressure Category:Fluid dynamics Category:Aerospace engineering

Hull (ship)

A hull is the body or frame of a ship or boat. It is a central concept in water vessels. The hull is essentially what keeps the water from entering the boat and acts as the walls and floor of the vessel. Nearly all watercraft, from small boats to the largest ships adhere to one general class of hull shapes that serve the needs of stability and efficient propulsion, featuring
- horizontal cross-sections that have narrow, usually pointed, fronts (at the bow),
- smooth widening from the bow until roughly the middle (the beam), and often narrowing smoothly but usually significantly to the extreme end (the stern), whose width may range from a large to an insignificant fraction of the beam width), and
- characteristic vertical cross-sections perpendicular to the beam. Such a cross section will usually feature
- an open top on a small boat (kayaks being the most familar exceptions), or a level deck (with various superstructures) on large boats or on ships,
- below that level, possibly widening and/or narrowing to some extent, smoothly, down the relatively sharp bend called the "knees",
- below the knees, either having a relatively flat bottom or narrowing smoothly to an angled seam at the center, and
- usually featuring either a keel or retractable centerboard at that centerline, or retractable sideboards roughly vertical and close to the most vertical portion of the hull. Nevertheless, other general shapes are feasible; the coracle is a relatively extreme example, and many cargo barges, with all cross-sections close to rectangular, are a radical departure from both the coracle and the tapered hulls described above. Large ships have a bulbous bow to reduce effective drag and thus increase fuel efficiency. Especially important in hulls constructed from materials that are denser than water, such as steel, the hull traps a volume of air that lowers the overall density of the vessel, providing buoyancy so it floats. Hulls constructed of materials that are less dense than water, such as some types of wood, will float even when full of water, barring sufficient weight of heavier-than-water cargo and superstructure. Hulls of the earliest design are thought to have each consisted of a hollowed out tree bole: in effect the first canoes. Hull construction then proceeded to keeled hulls, use of ballast, and on to modern double steel hulls with waterproof sections. In the case of new sailing-ship designs as of 2004, hulls are often made of layers of foam and plastic, forming composite hulls, with a minimum of weight. Variations on the single hull can be found with outriggers, and multihull craft with at least one hull nested inside the outermost one. Hull construction is usually performed in a dry dock or on a slipway.

See also


- double hull Category:Ship construction Category:Sailing ship elements ja:船体

Bow (boat)

A boat is a watercraft, usually smaller than most ships. Some boats are commonly carried by a ship or on land using trailers. A boat consists of one or more buoyancy structures called hulls and some system of propulsion, such as a screw, oars, paddles, a setting pole, a sail, paddlewheels or a water jet.

Parts of a Boat

The roughly horizontal but cambered structures spanning the hull of the boat are referred to as the "deck". In a ship, there would be several but a boat is unlikely to have more than one. The similar but usually lighter structure which spans a raised cabin is a coarch-roof. The "floor" of a cabin is properly known as the sole but is more likely to be called the floor. (A floor is properly, a structural member which ties a frame to the keelson and keel.) The underside of a deck is the deck head. The vertical surfaces dividing the internal space are "bulkheads". Some are important parts of the vessel's structure. The front of a boat is called the bow or prow. The rear of the boat is called the stern. The right side is starboard and the left side is port. It is somewhat risible in modern practice to call the command area of a large boat the "bridge". It is the cockpit or wheelhouse, depending on its design. The compartments housing a toilet, and the toilet itself, are known as the "heads", and a trip to this area is a "head call". In the old days, cordage intended for the delicate hands of a yacht's owner was of linen, later cotton. Therefore cordage used to control a sailing boat, tends to be referred to as "line" rather than rope. Most have specific names, but in general, lines used for raising things like sails and flags are "halyards" while the principal ones for adjusting the positions of the sails are called "sheets". All the lines and wire collectively are referred to as "rigging". That which is set up in the yard and left is standing rigging. That which is adjustable in use is running rigging. For example, a forestay is standing rigging and a sheet or a halyard is part of the running rigging.

Types of Boats

water jet
- Bangca
- Bateau
- Barge
- Cabin Cruiser
- Canoe
- Catamaran
- Cape Islander
- Catboat
- Coracle
- Cruiser
- Cutter
- Dhow
- Dinghy
- Dory
- Durham Boat
- Dutch Barge
- Felucca
- Ferry
- Folding boat
- Go-fast boat
- Gondola
- Houseboat
- Inflatable boat Inflatable boat]
- Jetboat, Jetski
- Jonsboat
- Junk
- Kayak
- Ketch
- Lifeboat
- Log boat
- Luxemotor
- Motorboat
- Narrowboat
- Norfolk wherry
- Outrigger canoe
- Padded V-hull
- Pinnace
- Pirogue
- Powerboat Powerboat
- Raft
- Rigid-hulled inflatable boat (RIB)
- Rowboat, rowing boat
- Sailboat, sailing boat
- Sampan
- Schooner
- Scow
- Sharpie
- Skiff
- Sloop
- Submarine
- Swift boat
- Tjalk
- Trimaran
- Tugboat
- U-boat
- Water taxi
- Whaleboat
- Yacht
- Yawl Yawl

Unusual types of boats

Unusual floating vehicles have been used for sports purposes as well. For example, the Bathtub Boat is used in "bathtub races" in many cities, although it originated in Nanaimo, BC, Canada.

Unusual uses of the word "Boat"


- Often in rowing as a racing-type competitive sport, "boat" means the crew and "shell" means the craft. So a university might refer to its first boat, meaning the rowers who make up their best team, rather than their best piece of equipment.
- A submarine is generally referred to as a boat rather than a ship. This dates from the early days of submarine warfare, when submarines were essentially motor torpedo boats which could submerge. In the modern combat environment where a typical attack submarine is the size of a destroyer and equipped with either a nuclear reactor or air independent propulsion which can allow it to stay submerged for months or weeks (and boomers are even larger, on the order of old-style battleships), this use is something of an anachronism.
- A ship can be informally known as a boat, especially by its crew. This use is uncommon in the case of a warship.
- In Great Lakes shipping, "boat" refers to any vessel, even one which would normally be considered a "ship" on the ocean.
- In some versions of cockney rhyming slang, "boat" means face, from "boat race".
- The term "gravy boat" is used to describe a small jug used to dispense meat gravy at the dining table. Similarly: "sauce boat".
- A boat can also be one of the massive cars manufactured in America from the 1950s through the 1970s.
- A boat, short for full-boat is another term for a full-house in the card game poker.

See also


- Boat building
- Cruising
- Electric boats
- Jet boat
- Jet sprint boat racing
- Offshore powerboat racing
- Sport
- Yachting

External links


- [http://www.boatingdir.com Boating Directory]
- [http://www.cronab.demon.co.uk/china.htm The Rise and Fall of 15th Century Chinese Seapower]
- [http://www.barges.org DBA - Dutch Barge Association] Living aboard ex-commercial barges or any other type of broad-beam inland waterways craft Category:Vehicles Category:Water transport
- ja:船 simple:Boat

Drag (physics)

:This page is about forces which tend to slow a moving object. For other uses, see Drag (disambiguation). For a solid object moving through a fluid or gas, drag is the sum of all the aerodynamic or hydrodynamic forces in the direction of the external fluid flow. It therefore acts to oppose the motion of the object, and in a powered vehicle it is overcome by thrust. Types of drag are generally divided into three categories: parasitic drag, lift-induced drag and wave drag. Parasitic drag includes form drag, skin friction and interference drag. Lift-induced drag is only relevant when wings or a lifting body are present, and is therefore usually discussed only in the aviation perspective of drag. Beyond these two kinds of drag there is a third kind of drag, called wave drag, that occurs when the solid object is moving through the fluid at or near the speed of sound in that fluid. The overall drag of an object is characterized by a dimensionless number called the drag coefficient, and is calculated using the drag equation. Assuming a constant drag coefficient, drag will vary as the square of velocity. Thus, the resultant power needed to overcome this drag will vary as the cube of velocity. The standard equation for drag is one half the coefficient of drag multiplied by the fluid density, the cross sectional area of your specified item, and the square of the velocity Wind resistance is a layman's term used to describe drag. Its use is often vague, and is usually used in a relative sense (e.g. A badminton shuttlecock has more wind resistance than a squash ball).

See also


- Atmospheric drag
- Drag Resistant Aerospike
- Gravity drag
- Added mass Category:Aerodynamics Category:Force ja:抗力

Horizontal stabilizer

Stabilizer (Stabiliser in UK English) may mean:
- Stabilizer (aircraft), surfaces to help keep aircraft under control
- Stabilizer (chemistry), a substance added to prevent unwanted change in state of another substance
- Stabilizer (ship), fins on ships to counteract roll
- Stabilization is a process to help prevent shock in sick or injured people
- Stabilizer, another name for bicycle training wheels
- Stabilizer in mathematics is a concept concerning group action
- Stabilizer is a type of food additive
- Stabilizer is a kind of voltage regulator in electronics
- Gun stabilizer, a device that helps a moving tank's gunner to aim the gun
- Mood stabilizer, a kind of psychiatric medication Category:Mathematical disambiguation

Engine

An engine is something that produces some effect from a given input. The origin of engineering was the working of engines. There is an overlap in English between two meanings of the word "engineer": 'those who operate engines' and 'those who design and construct new items'.

Usage of the term

In original usage, an engine was any sort of mechanical device. The term "gin" in cotton gin is a short form of this usage. Practically every device from the industrial revolution was referred to as an engine, and this is where the steam engine gained its name. This form of the term has recently come into use once again in computer science, where terms like search engine, "3-D graphics rendering engine" and "text-to-speech engine" are common. The earliest mechanical computing device was called the difference engine; Military devices such as catapults are referred to as siege engines. In more recent usage, the term is typically used to describe devices that perform mechanical work, follow-ons to the original steam engine. In most cases the work is supplied by exerting a torque, which is used to operate other machinery, generate electricity, pump water or compress gas. In the context of propulsion systems, an air breathing engine is one that uses atmospheric air to oxidise the fuel carried, rather than carrying an oxidiser, as in a rocket. Theoretically, this should result in a better specific impulse than for rocket engines.

History of engines

Antiquity

While chemical and electrical engines of enormous power dominate the modern world, engines themselves are not new. Engines using human power, animal power, water power, wind power and even steam power date back to antiquity. Human power was focused by the use of simple engines, such as the capstan, windlass or treadmill, and with ropes, pulleys, and block and tackle arrangements, this power was transmitted and multiplied. These were commonly used in cranes and aboard ships during Ancient Greece, and in mines, water pumps and siege engines in Ancient Rome. Early oared warships used human power augmented by the simple engine of the lever -- the oar itself. The writers of those times, including Vitruvius, Frontinus and Pliny the Elder, treat these engines as commonplace, so their invention may be far more ancient. By the 1st century AD, various breeds of cattle and horses were used in mills, using machines similar to those powered by humans in earlier times. According to Strabo, a water powered mill was built in Kaberia in the kingdom of Mithridates in the 1st century BC. Use of water wheels in mills slowly spread through Europe over the next few centuries. Some were quite complex, with aqueducts, dams, and sluices to maintain and channel the water, and systems of gears, or toothed-wheels made of wood with metal, used to regulate the speed of rotation. In a poem by Ausonius in the 4th century, he mentions a stone-cutting saw powered by water. Hero of Alexandria demonstrated both wind and steam powered machines in the 1st century, although it's not known if these were put to any practical use until much later. In the broadest sense of the term, internal combustion engines can be said to have been invented in China, with the invention of fireworks during the Song dynasty, with some sources putting this invention a thousand years earlier still. Monumental structures of Ancient Egypt, it has been purported, might have been constructed with engines, especially in the transport and/or raising of some 15 to over 100 ton stone blocks. Electrical devices have been purported to have been discovered in digs in Iraq and Egypt and on ancient Egyptian walls and writings.

Modern

English inventor Sir Samuel Morland allegedly used gunpowder to drive water pumps in the 17th century. For more conventional, reciprocating internal combustion engines the fundamental theory for two-stroke engines was established by Sadi Carnot, France, 1824, whilst the American Samuel Morey received a patent on April 1, 1826. Automotive production down the ages has required a wide range of energy-conversion systems. These include electric, steam, solar, turbine, rotary, and different types of piston-type internal combustion engines. The gasoline internal combustion engine, operating on a four-stroke Otto cycle, has traditionally been the most successful for automobiles, while diesel engines are widely used for trucks and buses. However, in the twenty first century the diesel engine has been increasing in popularity with automobile owners. This is partially due to the improvement of engine control systems (computers) and forced induction (turbos and superchargers), giving modern diesel engines the same power charachteristics as gasoline engines. This is especially evident with the popularity of diesel engines in Europe. The internal combustion engine was originally selected for the automobile due to its flexibility over a wide range of speeds. Also, the power developed for a given weight engine was reasonable; it could be produced by economical mass-production methods; and it used a readily available, moderately priced fuel--gasoline. In today’s world, there has been a growing emphasis on the pollution producing features of automotive power systems. This has created new interest in alternate power sources and internal-combustion engine refinements that were not economically feasible in prior years. Although a few limited-production battery-powered electric vehicles have appeared from time to time, they have not proved to be competitive owing to costs and operating characteristics. However, the gasoline engine, with its new emission-control devices to improve emission performance, has not yet been challenged significantly. The first half of the twentieth century saw a trend to increase engine power, particularly in the American models. Design changes incorporated all known methods of raising engine capacity, including increasing the pressure in the cylinders to improve efficiency, increasing the size of the engine, and increasing the speed at which power is generated. The higher forces and pressures created by these changes created engine vibration and size problems that led to stiffer, more compact engines with V and opposed cylinder layouts replacing longer straight-line arrangements. In passenger cars, V-8 layouts were adopted for all piston displacements greater than 250 cubic inches (4 litres). Smaller cars brought about a return a to smaller engines, the four- and six-cylinder designs rated as low as 80 horsepower (60 kW), compared with the standard-size V-8 of large cylinder bore and relatively short piston stroke with power ratings in the range from 250 to 350 hp (190 to 260 kW). The automobile motor from Europe had a bigger range, varying from 1to12 cylinders with corresponding differences in overall size, weight, piston displacement, and cylinder bores. Four cylinders and power ratings from 19 to 120 hp (14 to 90 kW) was followed in a majority of the models. Several three-cylinder, two-stroke-cycle models were built while most engines had straight or in-line cylinders. There were several V-type models and horizontally opposed two- and four-cylinder makes too. Overhead camshafts were frequently employed. The smaller engines were commonly air-cooled and located at the rear of the vehicle; compression ratios were relatively low. The 1970s and '80s saw an increased interest in improved fuel economy which brought in a return to smaller V-6 and four-cylinder layouts, with as many as five valves per cylinder to improve efficiency. Air-breathing engines include:
- Internal combustion engine
- Jet engine
- Ramjet
- Scramjet
- Pulse detonation engine
- Pulse jet engine
- Liquid air cycle engine

See also


- Spacecraft propulsion
- Aircraft engine
- Air engine
- Car engine
- Electric motor
- Motorcycle Engine
- External-combustion engine
  - Steam engine
  - Steam turbine
  - Stirling engine
- Internal-combustion engine
  - Controlled Combustion Engine
  - Gas turbine
  - Jet engine
  - Rocket
  - Diesel engine
  - Gasoline engine
  - HCCI engine
  - Radial engine
  - Stelzer engine
  - Orbital engine
  - Wankel engine
  - Quasiturbine
- Outboard motor
- Timeline of motor and engine technology
- Turbine
- Water turbine

References


- J. G. Landels, Engineering in the Ancient World, ISBN 0520041275

External links


- [http://auto.howstuffworks.com/engine.htm How stuff works : Cars Engines]
- [http://www.keveney.com/Engines.html Engines working. Animation]
- Category:Mechanical engineering ja:エンジン

Internal combustion

The internal combustion engine is a heat engine in which combustion occurs in a confined space called a combustion chamber. Combustion of a fuel creates high temperature/pressure gases, which are permitted to expand. The expanding gases are used to directly move a piston, turbine blades, rotor(s), or the engine itself thus doing useful work. Internal combustion engines can be powered by any fuel that can be combined with an "oxidizer" in the chamber. By way of contrast, an external combustion engine such as a steam engine does work when the combustion process heats a separate working fluid, such as water or steam, which then in turn does work. Jet engines, most rockets and many gas turbines are strictly classed as internal combustion engines, but the term internal combustion engine is also used to refer specifically to reciprocating engines, Wankel engines and similar designs in which combustion is intermittent. Today, in some published discussions, internal combustion engine is abbreviated to the acronym ICE.

History

Wankel engine English inventor Sir Samuel Morland used gunpowder to drive water pumps in the 17th century. For more conventional, reciprocating internal combustion engines the fundamental theory for two-stroke engines was established by Sadi Carnot in France in 1824, whilst the American Samuel Morey received a patent on April 1, 1826 for a "Gas Or Vapor Engine". The Italians Eugenio Barsanti and Felice Matteucci patented the first working, efficient version of an internal combustion engine in 1854 in London (pt. Num. 1072). Despite these and other attempts, it wasn't until 1859 that the Frenchman Étienne Lenoir (1822 - 1900) designed an engine that ran on a mixture of explosive gas and air. In 1860, Jean Joseph Etienne Lenoir produced a gas-fired internal combustion engine not dissimilar in appearance to a steam beam engine. This closelly resembled a horizontal double acting steam engine, with cylinders, pistons, connecting-rods and fly wheel in which the gas essentially took the place of the steam. In 1870 in Vienna Siegfried Marcus put the first mobile gasoline engine on a handcart. Nikolaus Otto working with Gottlieb Daimler and Wilhelm Maybach in the 1870's developed the four-stroke cycle (Otto cycle) engine.

Applications

Internal combustion engines are most commonly used for mobile propulsion systems. In mobile scenarios internal combustion is advantageous, since it can provide high power to weight ratios together with excellent fuel energy-density. These engines have appeared in almost all cars, motorbikes, many boats, and in a wide variety of aircraft and locomotives. Where very high power is required, such as jet aircraft, helicopters and large ships, they appear mostly in the form of gas turbines. They are also used for electric generators and by industry. For low power mobile and many non-mobile applications an electric motor is a competitive alternative. In the future, electric motors may also become competitive for most mobile applications. However, the high cost and weight and poor energy density of batteries and lack of affordable onboard electric generators such as fuel cells has largely restricted their use to specialist applications.

Operation

All internal combustion engines depend on the exothermic chemical process of combustion: the reaction of a fuel, typically with air, although other oxidisers such as nitrous oxide may be employed. Also see stoichiometry. The most common fuels in use today are made up of hydrocarbons and are derived from petroleum. These include the fuels known as diesel, gasoline and liquified petroleum gas. Most internal combustion engines designed for gasoline can run on natural gas or liquified petroleum gases without modifications except for the fuel delivery components. Liquid and gaseous biofuels of adequate formulation can also be used. Some have theorized that in the future hydrogen might replace such fuels. Furthermore, with the introduction of hydrogen fuel cell technology, the use of internal combustion engines may be phased out. The advantage of hydrogen is that its combustion produces only water. This is unlike the combustion of hydrocarbons, which also produces carbon dioxide, a major cause of global warming, as well as carbon monoxide, resulting from incomplete combustion. The big disadvantage of hydrogen in many situations its storage. Liquid hydrogen has extremely low density- 14 times lower than water and requires extensive insulation, whilst gaseous hydrogen requires very heavy tankage. While hydrogen is light and therefore has a higher specific energy, the volumetric efficiency is still roughly five times lower than petrol. This is why hydrogen must be compressed if there is to be a useful amount of stored energy. All internal combustion engines must have a means of ignition to promote combustion. Most engines use either an electrical or a compression heating ignition system. Electrical ignition systems generally rely on a lead-acid battery and an induction coil to provide a high voltage electrical spark to ignite the air-fuel mix in the engine's cylinders. This battery can be recharged during operation using an alternator driven by the engine. Compression heating ignition systems (Diesel engines and HCCI engines) rely on the heat created in the air by compression in the engine's cylinders to ignite the fuel. Once successfully ignited and burnt, the combustion products (hot gases) have more available energy than the original compressed fuel/air mixture (which had higher chemical energy). The available energy is manifested as high temperature and pressure which can be translated into work by the engine. In a reciprocating engine, the high pressure product gases inside the cylinders drive the engine's pistons. Once the available energy has been removed the remaining hot gases are vented (often by opening a valve or exposing the exhaust outlet) and this allows the piston to return to its previous position (Top Dead Center - TDC). The piston can then proceed to the next phase of its cycle (which varies between engines). Any heat not translated into work is a waste product and is removed from the engine either by an air or liquid cooling system.

Parts

heat The parts of an engine vary depending on the engine's type. For a four-stroke engine, key parts of the engine include the crankshaft (purple), one or more camshafts (red and blue) and valves. For a two-stroke engine, there may simply be an exhaust outlet and fuel inlet instead of a valve system. In both types of engines, there are one or more cylinders (grey and green) and for each cylinder there is a spark plug (darker-grey), a piston (yellow) and a crank (purple). A single sweep of the cylinder by the piston in an upward or downward motion is known as a stroke and the downward stroke that occurs directly after the air-fuel mix in the cylinder is ignited is known as a power stroke. A Wankel engine has a triangular rotor that orbits in an epitroichoidal (figure 8 shape) chamber around an eccentric shaft. The four phases of operation (intake, compression, power, exhaust) take place in separate locations, instead of one single location as in a reciprocating engine. A Bourke Engine uses a pair of pistons integrated to a scotch yoke that transmits reciprocating force through a specially designed bearing assembly to turn a crank mechanism. Intake, compression, power, and exhaust all occur in each stroke of this yoke.

Classification

There is a wide range of internal combustion engines corresponding to their many varied applications. Likewise there is a wide range of ways to classify internal-combustion engines, some of which are listed below. Although the terms sometimes cause confusion, there is no real difference between an "engine" and a "motor." At one time, the word "engine" (from Latin, via Old French, ingenium, "ability") meant any piece of machinery. A "motor" (from Latin motor, "mover") is any machine that produces mechanical power. Traditionally, electric motors are not referred to as "engines," but combusion engines are often referred to as "motors."

Principles of operation

electric motor Reciprocating:
- Two-stroke engine
- Four-stroke engine
- Bourke Engine Rotary:
- Demonstrated:
  - Wankel engine
- Proposed:
  - orbital engine
  - quasiturbine Continuous combustion:
- gas turbine
- jet engine
- rocket engine

Engine cycle

Engines based on the two-stroke cycle use two strokes (one up, one down) for every power stroke, relying on the action of the bottom of the piston within the crankcase to help move the fuel-air mixture, and are used where small size and weight are important, such as snowmobiles, lawnmowers, mopeds, outboard motors and some motorcycles. Gasoline two-stroke engines are generally louder, less efficient, more polluting, and smaller than their four-stroke counterparts, although large two-stroke diesel engines are not subject to these complaints and are used in many applications, for instance some locomotives built by EMD. Engines based on the four-stroke cycle or Otto cycle have one power stroke for every four strokes (up-down-up-down) and are used in cars, larger boats and many light aircraft. They are generally quieter, more efficient and larger than their two-stroke counterparts. There are a number of variations of these cycles, most notably the Atkinson and Miller cycles. Most truck and automotive Diesel engines use a four-stroke cycle, but with a compression heating ignition system it is possible to talk separately about a diesel cycle. The Wankel engine operates with the same separation of phases as the four-stroke engine (but with no piston strokes, would more properly be called a four-phase engine), since the phases occur in separate locations in the engine; however like a two-stroke piston engine, it provides one power 'stroke' per revolution per rotor, giving it similar space and weight efficiency. The Bourke cycle's combustion phase more closely approximates constant volume combustion than either four stroke or two stroke cycles do. It also uses less moving parts, hence needs to overcome less friction than the other two reciprocating types have to. In addition, its greater expansion ratio also means more of the heat from its combustion phase is utilized than is used by either four stroke or two stroke cycles.

Fuel and oxidiser types

Fuels used include gasoline (aka petrol), Liquified Petroleum Gas, Vapourized Petroleum Gas, Compressed Natural Gas, hydrogen, diesel fuel, JP18 (jet fuel), landfill gas, biodiesel, peanut oil, ethanol, methanol (methyl or wood alcohol). Engines that use gases for fuel are called gas engines and those that use liquid hydrocarbons are called oil engines. However, gasoline engines are often called gas engines for short. The only limitations are that the fuel must be easily transportable through the fuel system to the combustion chamber, and that the fuel release sufficient energy in the form of heat upon combustion to make use of the engine practical. The oxidiser is typically air, but can be pure oxygen, nitrous oxide or hydrogen peroxide. Other chemicals such as chlorine or fluorine have seen experimental use; but mostly are impractical. Diesel engines are generally heavier, noisier and more powerful at lower speeds than gasoline engines. They are also more fuel-efficient in most circumstances and are used in heavy road-vehicles, some automobiles (increasingly more so for their increased fuel-efficiency over gasoline engines), ships and some locomotives and light aircraft. Gasoline engines are used in most other road-vehicles including most cars, motorcycles and mopeds. Note that in Europe, sophisticated diesel-engined cars are far more prevalent, representing around 40% of the market. Both gasoline and diesel engines produce significant emissions. There are also engines that run on hydrogen, methanol, ethanol, liquefied petroleum gas (LPG) and biodiesel. Paraffin and Tractor vaporising oil (TVO) engines are no longer seen. Tractor vaporising oil

Cylinders

Internal combustion engines can contain any number of cylinders with numbers between one and twelve being common, though as many as 28 have been used. Having more cylinders in a engine yields two potential benefits: First. the engine can have a larger displacement with smaller individual reciprocating masses (that is, the mass of each piston can be less) thus making a smoother running engine (since the engine tends to vibrate as a result of the pistons moving up and down). Second, with a greater displacement and more pistons, more fuel can be combusted and there can be more combustion events (that is, more power strokes) in a given period of time, meaning that such an engine can generate more torque than a similar engine with fewer cylinders. The down side to having more pistons is that, over all, the engine will tend to weigh more and tend to generate more internal friction as the greater number of pistons rub against the inside of their cylinders. This tends to decrease fuel efficiency and rob the engine of some of its power. For high performance gasoline engines using current materials and technology (such as the engines found in modern automobiles), there seems to be a break point around 10 or 12 cylinders, after which addition of cylinders becomes an overall detriment to performance and efficiency, although exceptions such as the W-16 engine from Volkswagen exist.
- Most car engines have four to eight cylinders, with some high performance cars having ten, twelve, or even sixteen, and some very small cars and trucks having two or three. In previous years some quite large cars, such as the DKW and Saab 92, had two cylinder, two stroke engines.
- Radial aircraft engines, now obsolete, had from five to 28 cylinders. A row contains an odd number of cylinders, so an even number indicates a two- or four-row engine.
- Motor cycles commonly have from one to four cylinders, with a few high performance models having six.
- Snowmobiles usually have two cylinders. Some larger (not necessarily high-performance, but also touring machines) have four.
- Small appliances such as chainsaws and domestic lawn mowers most commonly have one cylinder, although two-cylinder chainsaws exist.

Ignition system

Internal combustion engines can be classified by their ignition system. Today most engines use an electrical or compression heating system for ignition. However outside flame and hot-tube systems have been used historically. Nikola Tesla gained one of the first patents on the mechanical ignition system with , "Electrical Igniter for Gas Engines", on 16 August 1898.

Fuel systems

Often for simpler reciprocating engines a carburetor is used to supply fuel into the cylinder. However, exact control of the correct amount of fuel supplied to the engine is impossible. Larger gasoline engines such as used in cars have mostly moved to Fuel injection systems. LPG engines use a mix of Fuel injection systems and closed loop carburetors. Diesel engines always use fuel injection. Other internal combustion engines like Jet engines use burners, and rocket engines use various different ideas including impinging jets, gas/liquid shear, preburners and many other ideas.

Engine configuration

Internal combustion engines can be classified by their configuration which affects their physical size and smoothness (with smoother engines producing less vibration). Common configurations include the straight or inline configuration, the more compact V configuration and the wider but smoother flat or boxer configuration. Aircraft engines can also adopt a radial configuration which allows more effective cooling. More unusual configurations, such as "H", "U", "X", or "W" have also been used. Multiple-crankshaft configurations do not necessarily need a cylinder head at all, but can instead have a piston at each end of the cylinder, called an opposed piston design. This design was used in the Junkers Jumo 205 diesel aircraft engine, using two crankshafts, one at either end of a single bank of cylinders, and most remarkably in the Napier Deltic diesel engines, which used three crankshafts to serve three banks of double-ended cylinders arranged in an equilateral triangle with the crankshafts at the corners. It was also used in single-bank locomotive engines, and continues to be used for marine engines, both for propulsion and for auxiliary generators. The Gnome Rotary engine, used in several early aircraft, had a stationary crankshaft and a bank of radially arranged cylinders rotating around it.

Engine capacity

An engine's capacity is the displacement or swept volume by the pistons of the engine. It is generally measured in litres or cubic inches for larger engines and cubic centimetres (abbreviated to cc's) for smaller engines. Engines with greater capacities are usually more powerful and provide greater torque at lower rpms but also consume more fuel. Apart from designing an engine with more cylinders, there are two ways to increase an engine's capacity. The first is to lengthen the stroke and the second is to increase the piston's diameter. In either case, it may be necessary to make further adjustments to the fuel intake of the engine to ensure optimal performance. An engine's quoted capacity can be more a matter of marketing than of engineering. The Morris Minor 1000, the Morris 1100, and the Austin-Healey Sprite Mark II all had engines of the same stroke and bore according to their specifications, and were from the same maker. However the engine capacities were quoted as 1000cc, 1100cc and 1098cc respectively in the sales literature and on the vehicle badges.

Engine pollution

Generally internal combustion engines, particularly reciprocating internal combustion engines, produce moderately high pollution levels, due to incomplete combustion of carbonaceous fuel, leading to carbon monoxide and some soot along with oxides of nitrogen & sulphur and some unburnt hydrocarbons depending on the operating conditions and the fuel/air ratio. Diesel engines produce a wide range of pollutants including aerosols of many small particles that are believed to penetrate deeply into human lungs.
- Many fuels contain sulfur leading to sulfur oxides (SOx) in the exhaust, promoting acid rain.
- The high temperature of combustion creates greater proportions of nitrogen oxides (NOx), demonstrated to be hazardous to both plant and animal health.
- Net carbon dioxide production is not a necessary feature of engines, but since most engines are run from fossil fuels this usually occurs. If engines are run from biomass, then no net carbon dioxide is produced as the growing plants absorb as much, or more carbon dioxide while growing.
- Hydrogen engines only produce water, in theory.

Bibliography


- Singer, Charles Joseph; Raper, Richard, A history of technology : The Internal Combustion Engine, edited by Charles Singer ... [et al.], Clarendon Press, 1954-1978. pp.157-176[http://proxy.bib.uottawa.ca:2398/cgi/t/text/pageviewer-idx?c=acls&cc=acls&idno=heb02191.0005.001&q1=bicycle&frm=frameset&seq=5]

External links


- [http://www.keveney.com/Engines.html Animated Engines] - explains a variety of types
- [http://auto.howstuffworks.com/engine3.htm How Internal Combustion Works] - with animation Category:Energy conversion Category:Engines ja:内燃機関

Rolls Royce

Rolls-Royce is a set of companies, all deriving from the British automobile and aero-engine manufacturing company founded by Henry Royce and C.S. Rolls in 1906. The companies are:
- Rolls-Royce plc, by far the most significant in economic terms, is a British engineering firm specializing in turbine-based products, particularly aircraft engines, but has recently added marine propulsion and energy systems to its portfolio, providing a wide range of civil and military engineering products and services.
- Rolls-Royce Motor Cars Limited, a new manufacturer of luxury automobiles, owned by BMW, which started deliveries of its single model, the Phantom, in January 2003 (see below).
- Bentley Motors is the continuation of the original Rolls-Royce automobile division. Since 1998 the company has been owned by the Volkswagen Group. Rolls-Royce and Bentley cars have shared much mechanically since the 1931 takeover of Bentley by Rolls-Royce, often differing in little other than the radiator grille. Confusingly, from 2003 the company is no longer allowed to produce cars called Rolls-Royce, the trademarks being licensed to BMW, rather than to Volkswagen. Nicknames for Rolls-Royce cars are Rolls, Roller and Double R, although in Derby (where the headquarters of Rolls-Royce plc are located), the firm is universally known as Royce's. The term "The Rolls-Royce of x" is often used informally (Cadillac is the American version of the term) to describe anything that is the best of its type. The company is aggressive at protecting its trademarks whenever commercial use of the term is mentioned. (One noted example was a coachbuilder marketing the Custom Cloud - which used a Chevrolet Monte Carlo with Rolls-Royce cues. The company was forced to shut down production after a heated lawsuit.) Column-mounted automatic transmission shifters are still used today on all Rolls-Royces.

History

In 1884 Frederick Henry Royce started an electrical and mechanical business. He made his first car, a "Royce", in his Manchester factory in 1904. He was introduced to Charles Stewart Rolls in a Manchester hotel on the May 4 that year, and the pair agreed a deal where Royce would manufacture cars, to be sold exclusively by Rolls. A clause was added to the contract, stipulating the cars would be called "Rolls-Royce". The company was formed on March 15, 1906 and moved to Derby in 1908. The Silver Ghost (1906-1925) was the model responsible for the company's early great reputation. It had a 6-cylinder engine. 6173 were built. In 1921, the company opened a second factory in Springfield, Massachusetts, in the United States to help meet demand there. A further 1701 "Springfield Ghosts" were built there. This factory operated for 10 years, closing in 1931. Its chasis was used as a basis for the first british armoured car deployed in both World wars. During 1931, the company acquired rival car maker Bentley, whose finances were unable to weather the Great Depression. From then until 2002, Bentley and Rolls-Royce cars were often identical apart from the radiator grille and minor details. The company's first aero engine was the Eagle, built from 1914. Around half the aircraft engines used by the Allies in WW1 were made by Rolls-Royce. By the late 1920s, aero engines made up most of Rolls-Royce's business. Henry Royce's last design was the Merlin aero engine, which came out in 1935 although he had died in 1933. This was a development subsequent to the R engine, which had powered a record-breaking Supermarine S6B seaplane to almost 400mph in the 1931 Schneider Trophy.) The Merlin was a powerful V12 engine, and was fitted into many World War II aircraft: the British Hawker Hurricane, Supermarine Spitfire, De Havilland Mosquito (twin-engined), Avro Lancaster (4-engine), Vickers Wellington (2-engine); it also transformed the American P-51 Mustang into possibly the best fighter of its time, its Merlin engine built by Packard under license. Over 160,000 Merlin engines were produced. Rolls-Royce and Bentley car production moved to Crewe in 1946, and also Mulliner Park Ward, London in 1959 as the company started to build bodies for its cars for the first time—previously it had only built chassis, leaving the bodies to specialist coachbuilders. For the rest of the automotive history, see sections below. In the post-World War II period Rolls-Royce made significant advances in gas turbine engine design and manufacture. The Dart and Tyne turboprop engines were particularly important enabling airlines to cut journey times within several continents whilst jet airliners were introduced on longer services. The Dart engine was used in Argosy, Avro 748, Friendship, Herald and Viscount aircraft, whilst the more powerful Tyne powered the Atlantic, Transall, Vanguard and the SRN-4 hovercraft. Many of these turboprops are still in service. Amongst the jet engines of this period was the RB163 Spey which powers the Trident, BAC 1-11, Grumman Gulfstream II and Fokker F28. During the late 50's and 60's there was a significant rationalisation of the British aero-engine manufacturers, culminating in the merger of Rolls-Royce and Bristol Siddeley in 1966 (Bristol Siddeley had itself resulted from the merger of Armstrong-Siddeley and Bristol in 1959). Bristol, with its principal factory at Filton, near Bristol, had a strong base in military engines, including the Olympus, which was chosen for Concorde. Financial problems caused largely by development of the new RB211 turbofan engine led—after several cash subsidies—to the company being nationalized by the Heath government in 1971. (This delay has been blamed for the failure of the technically advanced Lockheed TriStar to succeed in the airliner marketplace, when it was beaten to launch by its competitor, the Douglas DC-10.) In 1973 the automobile business was spun off as a separate entity, Rolls-Royce Motors. The main business of aircraft and marine engines remained in public ownership until 1987, when it was privatised as Rolls-Royce plc, one of many privatisations of the Thatcher government. In 1980 Rolls-Royce Motor Cars was acquired by Vickers. In 1998 Vickers sold the company on to Volkswagen (see below). A year later Rolls-Royce plc acquired Vickers plc for £576m. Today Rolls-Royce engines continue to power many of the world's civil and military aircraft and the company has been particularly effective in reducing noise and adverse emissions from its aviation products, anticipating international regulations arising from community campaigns and improved environmental understanding. Unfortunately, the managing director of BMW announced on 8 May, 2005 that the sales of Rolls-Royce cars had fallen by 26% in only 6 months. BMW will seek to sell the company if the problems continue.

Rolls-Royce cars 1945-1998

2005 The major events in the company's history were:
- 1965: launch of the modern Silver Shadow.
- 1971: nationalization of the combined aero-engine and car company.
- 1973: privatization of the car division as Rolls-Royce Motor Cars.
- 1980: Rolls-Royce Motor Cars acquired by Vickers. Main cars in this period:
- Silver Dawn, 1949-1955.
- Silver Cloud, 1955-1966.
- Silver Shadow, 1965-1980. This was the first Rolls-Royce with a monocoque chassis. Started with a 6.23 L V8 engine, later expanded to 6.75 L. This shared its design with the Bentley T-series.
- Camargue, 1975-1986 with a Pininfarina body
- Silver Spirit, 1980-1994. This shared its design with the Bentley Mulsanne.
- Corniche, 1971-1996 (generations I - IV) Bentley models were produced mostly in parallel with the above cars. The Bentley Continental coupés (produced in various forms from the mid-1950s to the mid-1960s) did not have Rolls-Royce equivalents. Very expensive Rolls-Royce Phantom limousines were also produced. In this period other luxury car makers, such as Mercedes-Benz, BMW and (much later) Lexus, made many technical advances combining sporting abilities with high levels of comfort; this left Rolls-Royces looking old-fashioned in many ways.

The VW and BMW deal

In 1998 Vickers decided to sell the Rolls-Royce automobile business. Although Volkswagen Group also made offers for the company, the leading contender seemed to be BMW, who already supplied engines and other components for Rolls-Royce and Bentley cars. However their final offer of £340m was outbid by VW, who offered £430m. This was far from the end of the story though. Rolls-Royce plc, the aero-engine maker, decided it would license certain essential trademarks (the Rolls-Royce name and logo) not to VW but to BMW, with whom it had recently had joint business ventures. VW had bought rights to the "Spirit of Ecstasy" mascot and the shape of the radiator grille, but it lacked rights to the Rolls-Royce name in order to build the cars. Likewise, BMW lacked rights to the grille and mascot. BMW took out the option on the trademarks, licensing the name and "RR" logo for £40m, a deal that many commentators thought was a bargain for possibly the most valuable property in the deal. VW claimed that it had only really wanted Bentley anyway. BMW and VW arrived at a solution. For the period from 1998 to 2002, BMW would continue to supply engines for the cars, and would allow use of the names, but this would cease on January 1, 2003. On that date, only BMW would be able to name cars "Rolls-Royce", and VW's former Rolls-Royce/Bentley division would only build cars called "Bentley". Rolls Royce's convertible, the Corniche, ceased production in 2002. The British press, particularly the tabloids, expressed consternation that this symbol of British excellence was being sold to the Germans, and in such an undignified manner.

Rolls-Royce cars from 1998


- 1998-2002 Silver Seraph - This shared its design with the Bentley Arnage, which sold in much greater numbers.
- 1992-2003 Bentley Continental R - This 6.75 L 400bhp car ended production and has now been superseded by the Continental GT.
- 1995-2003 Bentley Azure - This 2-dr convertible was Bentley's most expensive model, with about half of the models being customized by Mulliner.
- 2000-2002 Corniche - This 2-dr convertible shared its design with the Bentley Azure, and was the most expensive Rolls-Royce until the introduction of the 2003 Phantom.
- 2003 Phantom - Launched in January 2003 at Detroit's North American International Auto Show, this is the first model of Rolls-Royce Motor Cars Limited, a BMW subsidiary having no technical or corporate connection with the original Rolls-Royce company, apart from the trademarks mentioned above. The car has a 6.75 L V12 engine from BMW, but most other components are unique to the car. Most parts are made in Germany, but the assembly and finishing is in a new factory in Goodwood, Sussex. The price starts at around £250,000. It is available in normal and extended wheelbase.

Prototype


- Rolls-Royce 100EX

Cars


- Rolls-Royce Camargue
- Rolls-Royce Corniche
- Rolls-Royce Phantom
- Rolls-Royce Silver Ghost
- Rolls-Royce Silver Cloud
- Rolls-Royce Silver Seraph
- Rolls-Royce Silver Shadow

External links


- [http://www.rolls-royce.com/ Rolls-Royce plc]
- [http://www.rolls-roycemotorcars.com/ Rolls-Royce Motor Cars]
- [http://www.netcarshow.com/rolls-royce/ Rolls-Royce picture galleries]
- [http://www.bentleymotors.co.uk/ Bentley Motors]
- [http://www.bentleyboys.com/rolls-royce_history.htm Bentley Boys Rolls-Royce History]
- [http://www.rrab.com/ Unofficial site from the Archives of K.-J. Roßfeldt]
- [http://y2u.co.uk/%26002_Images/Rolls_01.htm Photos of Rolls-Royce Centenary in Manchester - 4th May 2004]
- Category:Luxury car manufacturers Category:British automobile manufacturersCategory:Automobile manufacturers ja:ロールス・ロイス

Allison Engine Company

The Allison Engine Company was a US aircraft engine manufacturer. They are best known for the Allison V-1710 V-12 engine, which was the only high-powered US liquid-cooled inline engine design to see use during World War II. In the post-war era they carved out a niche early jet engines, and later turboshafts for helicopter use. In 1995 they were acquired by Rolls-Royce. Allison started as an engine and car "hot rodding" company servicing the Indianapolis Motor Speedway in Indianapolis. It's only regular production line item was steel-backed lead brushings, used as bearings in various aircraft engines. They also built various drive shafts, extensions and gear chains for high power engines, on demand. Another, smaller, business was the conversion of older Liberty engines to more powerful models, both for aircraft and marine use. In the late 1920s the US Army funded the development of a series of high-power inline engines, as part of their hyper engine series, which they intended to produce on Continental Motors' production lines. Allison's manager, N.H. Gilman, decided to experiment with their own high-power cylinder design. The result was presented to the Army in 1928, who turned down their development proposal. In 1929, shortly after the death of James Allison, the company was purchased by the Fisher Brothers, who instructed them to use the cylinder design for a six cylinder engine for a "family aircraft". Before work on this design had progressed very far, Fisher sold the company to General Motors, who ended development due to financial pressures of the Great Depression. Nevertheless Gilman pressed ahead with the cylinder design, building a "paper project" V-12 engine. The Army was once again uninterested, but instead suggested they try selling it to the US Navy. The Navy agreed to fund development of A and B models to a very limited degree for their airships, until the crash of the USS Macon in 1935, when their need for a 1,000hp engine disappeared. By this point the Army had become more interested, and asked Allison to continue with a new C model. The V-1710-C first flew on 14 December, 1936 in the Consolidated A-11A testbed. The V-1710-C6 successfully completed the Army 150 hour Type Test on 23 April, 1937, at 1,000 hp (750 kW), the first engine of any type to do so. By this point all of the other Army engine projects had been cancelled or withdrawn, leaving the V-1710 as the only modern inline available. It was soon found as the