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Ford Model T, 1927, regarded as the first affordable American automobile
Since the 1920s, nearly all cars have been mass-produced to meet market needs, so marketing plans often have heavily influenced automobile design. It was Alfred P. Sloan who established the idea of different makes of cars produced by one company, so buyers could "move up" as their fortunes improved.
Reflecting the rapid pace of change, makes shared parts with one another so larger production volume resulted in lower costs for each price range. For example, in the 1930s, LaSalles, sold by Cadillac, used cheaper mechanical parts made by Oldsmobile; in the 1950s, Chevrolet shared hood, doors, roof, and windows with Pontiac; by the 1990s, corporate drivetrains and shared platforms (with interchangeable brakes, suspension, and other parts) were common. Even so, only major makers could afford high costs, and even companies with decades of production, such as Apperson, Cole, Dorris, Haynes, or Premier, could not manage: of some two hundred American car makers in existence in 1920, only 43 survived in 1930, and with the Great Depression, by 1940, only 17 of those were left.[16]
In
See also: Automotive industry
Fuel and propulsion technologies
Auto rickshaws in
A CNG powered high-floor Neoplan AN440A, run on Compressed Natural Gas
See also: Alternative fuel vehicle
Most automobiles in use today are propelled by gasoline (also known as petrol) or diesel internal combustion engines, which are known to cause air pollution and are also blamed for contributing to climate change and global warming.[17] Increasing costs of oil-based fuels, tightening environmental laws and restrictions on greenhouse gas emissions are propelling work on alternative power systems for automobiles. Efforts to improve or replace existing technologies include the development of hybrid vehicles, and electric and hydrogen vehicles which do not release pollution into the air.
Diesel
Main article: Diesel engine
Diesel-engined cars have long been popular in
Gasoline
Main article: Petrol engine
2007 Mark II (BMW) Mini Cooper
Gasoline engines have the advantage over diesel in being lighter and able to work at higher rotational speeds and they are the usual choice for fitting in high-performance sports cars. Continuous development of gasoline engines for over a hundred years has produced improvements in efficiency and reduced pollution. The carburetor was used on nearly all road car engines until the 1980s but it was long realised better control of the fuel/air mixture could be achieved with fuel injection. Indirect fuel injection was first used in aircraft engines from
The hydrogen powered FCHV (Fuel Cell Hybrid Vehicle) was developed by
Bioalcohols and biogasoline
Ethanol, other alcohol fuels (biobutanol) and biogasoline have widespread use an automotive fuel. Most alcohols have less energy per liter than gasoline and are usually blended with gasoline. Alcohols are used for a variety of reasons - to increase octane, to improve emissions, and as an alternative to petroleum based fuel, since they can be made from agricultural crops.
Electric
Main articles:
The Henney Kilowatt, the first modern (transistor-controlled) electric car.
2007 Tesla electric powered Roadster
The first electric cars were built around 1832, well before internal combustion powered cars appeared.[19] For a period of time electrics were considered superior due to the silent nature of electric motors compared to the very loud noise of the gasoline engine. This advantage was removed with Hiram Percy Maxim's invention of the muffler in 1897. Thereafter internal combustion powered cars had two critical advantages: 1) long range and 2) high specific energy (far lower weight of petrol fuel versus weight of batteries). The building of battery electric vehicles that could rival internal combustion models had to wait for the introduction of modern semiconductor controls and improved batteries. Because they can deliver a high torque at low revolutions electric cars do not require such a complex drive train and transmission as internal combustion powered cars. Some post-2000 electric car designs such as the Venturi Fétish are able to accelerate from 0-
Steam
Main article: steam car
Steam power, usually using an oil- or gas-heated boiler, was also in use until the 1930s but had the major disadvantage of being unable to power the car until boiler pressure was available (although the newer models could achieve this in well under a minute). It has the advantage of being able to produce very low emissions as the combustion process can be carefully controlled. Its disadvantages include poor heat efficiency and extensive requirements for electric auxiliaries.[21]
Air
Main article: Compressed-air car
Tata/MDI OneCAT Air Car
A compressed air car is an alternative fuel car that uses a motor powered by compressed air. The car can be powered solely by air, or by air combined (as in a hybrid electric vehicle) with gasoline/diesel/ethanol or electric plant and regenerative braking. Instead of mixing fuel with air and burning it to drive pistons with hot expanding gases; compressed air cars use the expansion of compressed air to drive their pistons. Several prototypes are available already and scheduled for worldwide sale by the end of 2008. Companies releasing this type of car include Tata Motors and Motor Development International (MDI).
Gas turbine
In the 1950s there was a brief interest in using gas turbine (jet) engines and several makers including Rover and Chrysler produced prototypes. In spite of the power units being very compact, high fuel consumption, severe delay in throttle response, and lack of engine braking meant no cars reached production.
Rotary (Wankel) engines
Rotary Wankel engines were introduced into road cars by NSU with the Ro 80 and later were seen in the Citroën GS Birotor and several Mazda models. In spite of their impressive smoothness, poor reliability and fuel economy led to them largely disappearing. Mazda, beginning with the R100 then RX-2, has continued research on these engines, overcoming most of the earlier problems with the RX-7 and RX-8.
Rocket and jet cars
1 comment:
very nice.
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