Air powered vehicles

Tag : Compressed Air Can
Watch Tower: Air powered vehicles A compressed air vehicle is powered by an air engine. Compressedair vehicles use the expansion of compressed air to drive theirpistons- Dr SS Verma
We are living in a very mobile society so light utility vehicles(LUV) like bikes and cars are becoming very popular as easy meansof independent transportation for short distances. Petrol anddiesel which have been the main source of fuel for the history ofvehicles, are becoming more and more expensive and impractical(especially from an environmental standpoint). These factors areleading vehicle manufacturers to develop vehicles fueled byalternative energies. Though fuel less flying (like birds) ieflying based on the use of bio-energy and air power in theatmosphere seems to be almost impossible for human beings atpresent level of development but engineers are still fascinatedwith the enormous power associated with the human friendly and welltested source of energy ie air. One possible alternative to makeuse of this source is the air-powered vehicles. Engineers aredirecting their sincere efforts to make use of air as an energysource to run the LUVs which will make future bikes and light/smallcars running with air power for daily routine distances and thetravel will be free from pollution, petrol and cost effective.
Technology:
Mankind is making use of air power from centuries in windmills,sailing, balloon car, hot air balloon flying and hang gliding etc.The use of compressed air for storing energy is a method that isnot only efficient and clean, but also economical and compressedair has been used since the 19th century to power mine locomotives,and was previously the basis of naval torpedo propulsion. In 1903,the Liquid Air Company located in London manufactured a number ofcompressed air and liquified air cars. The major problem with thesecars and all compressed air cars was the lack of torque produced bythe "engines" and the cost of compressing the air. Recently severalcompanies have started to develop compressed air vehicles.Compressed air tanks store power really well but are lacking onpower density. They tie or beat batteries in the charge / rechargeefficiency and totally kill them on lifespan. Higher pressures aretheir big problem; while efficiency, cost, toxic chemicals, andlifespan are the big problems with chemical batteries.
A compressed air vehicle is powered by an air engine, usingcompressed air, which is stored in a tank. Instead of mixing fuelwith air and burning it in the engine to drive pistons with hotexpanding gases, compressed air vehicles (CAV) use the expansion ofcompressed air to drive their pistons. The principle ofcompressed-air propulsion seems very simple. Pressurize the storagetank, connect it to something very like a reciprocating steamengine, and off you go. At least you are spared the difficulties,both technical and medical, of using ammonia, petrol, or carbondisulphide as the working fluid. Manufacturers claim to havedesigned engine that is 90 percent efficient. The air is compressedat pressure about 150 times the rate you would put into car tyresor your bicycle. The tanks must be designed to safety standardsappropriate for a pressure vessel. The storage tank may be made ofsteel, aluminium, carbon fiber, Kevlar or other materials, orcombinations of the above. The fiber materials are considerablylighter than metals but generally more expensive. Metal tanks canwithstand a large number of pressure cycles, but must be checkedfor corrosion periodically. One company stores air in tanks at4,500 pounds per square inch (about 30 MPa) and hold nearly 3,200cubic feet (around 90 cubic metres) of air. The tanks may berefilled at a service station equipped with heat exchangers, or ina few hours at home or in parking lots, plugging the vehicle intoan on-board compressor. The cost of driving such a car is typicallyprojected to be around Rs.60 per 100 km, with a complete refill atthe "tank-station" at about Rs. 120 only.
Developments:
Jem Stansfield, an English inventor has been able to convert aregular scooter to a compressed air moped. This has been done byequipping the scooter with a compressed air engine and air tank.Jem Stansfield created the bike by strapping two high-pressuretanks onto the side of his Puch moped. The tanks are basicallyscuba tanks. He uses the electricity from his house to fill thetanks. The power is then "stored" there, much like a battery, readyfor use. The tanks used are carbon-fiber tanks of the sort used byfirefighters for oxygen. But still, they're far cheaper than eventhe lead acid battery used in car now. Of course, the compressorworks on electricity, so that's not always a clean power source butrecharging options at night or off peak will enhance the chances touse the power that would be wasted otherwise. The top speed isabout 18 mph, and it can only go 7 miles before the air pressureruns out and a lot more power could probably be pulled by tweakinghis configuration. A small gear on the end of the air drill,connected to the chain of the bike would make a much more elegantsolution.
Several companies are investigating and producing prototypes, andothers plan to offer air powered cars, buses and trucks. Thecompressed air is stored in carbon-fiber tanks that are built intothe chassis. As the air is released, the pressure drives pistonsthat power the engine and move the car, and the pistons compressthe air into a reservoir so that the process continues. Aftermaking a revolution by producing the world's cheapest car-Tata nano, India's largest automaker (Tata Motors) is set to start producingthe world's first commercial air-powered vehicle. The Air Car willmake use of compressed air, as opposed to the gas-and-oxygenexplosions of internal-combustion models, to push its engine'spistons. Zero Pollution Motors (ZPM) (USA) also expects to producethe world's first air-powered car for the United States by late2009 or early 2010. An earlier version of the car is noisy andslow, and a tiny bit cumbersome but then this vehicle will not becompeting with a Ferrari or Rolls Royce and the manufacturers arealso not seeking to develop a Formula One version of the vehicle.The aim of air powered vehicles is the urban motorist: deliveryvehicles, taxi drivers, and people who just use their vehicles tonip out to the shops. The latest air car is said to have come onleaps and bounds from the early model. It is said to be muchquieter, a top speed of 110 km/h (65 mph), and a range of around200 km before you need to fill the tanks up with air.