Steam car
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A steam car is a car powered by a steam engine.
[edit] Technology
A steam engine is an external combustion engine (ECE - the fuel is combusted outside the engine), as opposed to an internal combustion engine (ICE - the fuel is combusted within the engine). Gasoline-powered ICE cars are more efficient at about 25-28% efficiency, while steam cars will function at only 5-8% efficiency without add-ons. Fitted with appropriate add-ons, a steam engine can achieve efficiencies of around 50%, well above those achieved by ICEs. An additional benefit of the ECE is that the fuel is burned at atmospheric pressure so does not produce carbon monoxide and nitrogen oxide. Depending upon burner design, an ECE may also achieve complete combustion of the carbon in its fuel, thus avoiding pollution.
Steam-powered cars and electric cars outsold gasoline powered cars in many U.S. states prior to the invention of the electric starter. Before the electric starter was put into production by General Motors, internal combustion powered cars were started by hand-crank, which was difficult and occasionally dangerous, as improper cranking could cause a backfire capable of breaking the arm of the operator. Electric cars period were popular to some extent, but had a short range, and could not be charged on the road if the batteries ran low.
Early steam cars could take some time to start from cold, but once fully fired up and working pressure was attained, could be instantly driven off. The Doble Steam Car shortened the starting time very noticeably by incorporating a flash steam generator which heated a much smaller quantity of water as required in addition to lessening the severity of a steam leak to the smaller volume of stored steam. By 1923, Abner Doble had developed an automatic boiler and burner which allowed his steam cars to be started with the turn of a key and driven off in 40 seconds or less. In addition, the Doble managed to achieve 15 miles per gallon of kerosene despite weighing in excess of 5,000 lbs.
[edit] History
Nicolas-Joseph Cugnot constructed his "Fardier à vapeur" ("Steam wagon") in 1769, which was intended for use by the French Army as an artillery tractor to haul cannons. His vehicle was reported to be capable of pulling 4 tones, and of traveling at up to 4 km per hour. The heavy vehicle was of tricycle layout, with two rear wheels and a steerable front wheel controlled by a tiller. In 1771 his vehicle crashed into a brick wall in the world's first known automobile accident, which combined with budget problems ended the French Army's experiment with self-propelled vehicles.
In 1801 Richard Trevithick constructed a steam car which was equipped with an inside hearth boiler, with a vertical cylinder, the single piston moved the driving wheels by means of a crosshead. It was reported as weighing 1520 kg fully loaded, with a speed of 14.5 km an hour on the flat.
Regular intercity bus services by steam powered buses were started in England in the 1830s by Sir Goldsworthy Gurney and Walter Hancock among others, but the heavy road tolls imposed by the Turnpike Acts discouraged steam road vehicles and left the way clear for the horse bus companies. Those companies which continued directed their efforts towards traction engines and agricultural machines rather than road transport.
From 1861 onwards, harsh legislation virtually eliminated mechanically propelled vehicles from the roads of Great Britain for 30 years, the Locomotive Act of 1861 imposing restrictive speed limits on "road locomotives" of 5 mph in towns and cities, and 10 mph in the country. In 1865 the Locomotives Act of that year (the famous Red Flag Act) further reduced the speed limits to 4 mph in the country and just 2 mph in towns and cities, additionally requiring a man bearing a red flag to precede every vehicle. At the same time, the act gave local authorities the power to specify the hours during which any such vehicle might use the roads. The sole exceptions were street trams which from 1879 onwards were authorised under licence from the Board of Trade.
The first usable steam car appeared in 1899 from the Locomobile Company of Bridgeport, Connecticut which manufactured several thousand of its Runabout model in the period 1899 - 1905, designed around a motor design leased from the Stanley Steamer Company. The company ceased producing steam cars in 1903, and was acquired by Durant Motors in 1922.
The White Steamer was manufactured in Cleveland, Ohio from 1900 until 1910 by the White Company.
Perhaps the best known and best selling steam car was the Stanley Steamer, produced from 1896 to 1924. It used a compact fire-tube boiler mounted beneath the hood to power a simple double-acting two-piston engine. Because of the phenomenal torque available at all engine speeds, the steam car's engine was typically connected directly to the rear axle, with no clutch or transmission required. Until 1914, Stanley steam cars vented their exhaust steam directly to the atmosphere, necessitating frequent refilling of the water tank; after 1914, all Stanleys were fitted with a condenser, which considerably improved their water usage.
In 1906 the World Land Speed Record was broken by a Stanley steam powered car, piloted by Fred Marriot, which achieved 127 mph at Ormond Beach, Florida. This annual week-long "Speed Week" was the forerunner of today's Daytona 500.
Steam cars dropped off in popularity following the adoption of the electric starter, which eliminated the need for risky hand cranks to start gasoline powered cars. The introduction of mass production by Henry Ford, which hugely reduced the cost of owning a conventional automobiles, was also a strong factor in the steam car's demise as the Model T was both cheap and reliable.
Attempts were made to bring more advanced steam cars to market such as the Doble Steam Car, but they ultimately failed due to high cost (in the case of the Doble) and a perceived lengthy starting process, despite their economy and power.
[edit] Modern steam cars
As a result of the 1973 oil crisis, SAAB started a project in 1974 headed by Dr. Ove Platell which made a prototype steam powered car. It used an electronically-controlled 28 pound multi parallel circuit steam generator with 1 millimeter bore tubing and 16 gph firing rate which was intended to produce 160 horsepower, and which about the same size as a standard car battery. Lengthy start-up times were circumvented by a system using compressed air that was stored when the car was running and which powered the car upon starting until adequate steam pressure was built up. The engine used a conical rotary valve made from pure boron nitride. To conserve water, a hermetically sealed water system was used.
A company called Enginion AG has since 1996 been developing a system which they have named SteamCell. It produces steam almost instantly without an open flame, and takes 30 seconds to reach maximum power from a cold start. Their third prototype, ZEE03, was fitted in Volkswagen and Skoda Fabia autombiles. The ZEE03 was a two-stroke of 1000 cc displacement, producing up to 220 hp (500 nm). Exhaust emissions were far below the SULEV standard. Since the water was recirculated, the engine used steam instead of oil as a lubricant. However, Enginion found that the market was not ready for steam cars, so they opted instead to produce power generators based on the same technology.[1][2]
[edit] See also
[edit] External links
- Hybrid-Vehicle.org: The Steamers
- The British Steam Car Challenge (an ongoing project started in 1999 dedicated to breaking the land speed record for a steam powered vehicle)
- Car Club of Great Britain
