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Car that runs on air
Trends
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Car that runs on air It is for the first time that a car uses air as fuel and emits no harmful gases. It would be a revolutionary step in controlling pollution by fossil fuels. The working of these engines depends upon compressed air technology system (CAT’s) which is the registered trademark of MDI SA. It uses an innovative system to control the movement of 2nd generation pistons and a single crankshaft. Such piston works in two stages-motor stage and an intermediate stage of compression or expansion. The engine consists of four 2-stage pistons (Fig. 1) i.e. 8 compression and expansion chambers. These have two functions — (i)to compress the ambient air and refill the storage tanks and (ii) to make successive expansions thereby approaching isothermic expansion. The CAT’s engine can be equipped with dual energy systems. It can either run on fossil fuels (petroleum) or on compressed air. To achieve the dual aspect, a reheating mechanism is incorporated to get continuous combustion of petroleum. While running on petroleum, the compressor refills the air tanks to get it ready for compressed air mode. Some important components of the air-powered cars are: Compressed Air Tanks: The air tanks are made of carbon fibre, which is lighter and stronger as compared to steel. In case of a major accident, these tanks do not explode — rather get ruptured. These tanks can carry air at 300 bars of pressure to carbon fibre bottles in a thermoplastic lining. The tanks weigh just 35 kg and hold 100 litres of air. The MDI has signed an agreement with the European leader in aerospace, the Air Bus Industries for supply of compressed storage tanks, which conform to all safety regulations. Brake power recovery:
The MDI cars would be fitted with a range of modern system for various controls. For example, one mechanism would stop the engine when the car is stationary at traffic lights and junctions. Another interesting feature would be the pneumatic system, which recovers about 13 per cent of the power used. This system would be used for stopping the car. Refilling of vehicles: For facilitating the easy use of CAT’s vehicles, MDI has developed a number of ways of refilling. Firstly, the tanks can be refilled in the garage by plugging the car into a mains socket, at 230V, to feed the motor-alternator. The motor-alternator compresses the air with the help of motor compressor and it takes nearly 5 hr 30 min to refill the tank. Secondly, the tanks can be refilled at a service station like petroleum. As the air energy is very easy to store, MDI anticipates the installation of air filling stations. It will take just 3 minutes to refill a car tank (Fig 2). Thirdly, MDI is conducting experiments for using non-conventional energy sources for refilling. An Aeolian system based on windmills, compresses air solely with wind energy. It is completely pollution free and only involves huge initial investment and maintenance cost. |
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Trends Imagine a Dalek enunciating the following words: “buttery”, “herby”, “oaky”. OK, now try: “Sauvignon Blanc” or “Valpolicella.” Now imagine it is a Japanese Dalek. You may just have heard the future of wine tasting, one which might have the BBC’s famously adjectival wine-taster, Jilly Goolden, spluttering over her “gooseberry notes”. Researchers in the Far East have invented a robot that can check the chemical composition of wine and advise its owner of the best vino for their palette. The robot, devised by NEC System Technologies and Mie University, works by pointing an infrared sensor at
the tip of its left arm at a bottle. When it has identified the grape, the robot comments on the taste — for instance stating whether the Chardonnay is buttery or the Shiraz full-bodied. The machine can perform the same task for food, assessing the saltiness of cheese or distinguishing between bitter and sweet apples. But it is the electro-mechanical sommelier’s wine-tasting prowess that has most excited its creators. “There are all kinds of robots out there doing many different things. But we decided to focus on wine because that seemed like a real challenge,” said Hideo Shimazu, of NEC System Technology.“Wines are notoriously similar in their spectral fingerprints. The variation this robot detects is very subtle.” By arrangement with The Independent, London |
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THIS UNIVERSE
A flame has different colours at the top, the middle and the bottom. Why? Colours arise from emissions from different constituents of the burning vapour. They are due to excitation of atoms to higher atomic levels and their de-excitation to lower energy states. Therefore they would depend on the material that is being burnt, but also on the temperature of the flame at a certain position. A flame is produced by a combustible gas being generated through heating, or supplied initially, mixing with an adequate supply of oxygen. But just this will not be able to produce the kind of flames we see. We also need gravity and the resultant convection of hot gases upwards. [This convection would be absent in a weightless situation and therefore the flames seen on earth are not possible while travelling in a satellite]. This results in a situation where the hottest part of the flame is at the top. For a gas burner, it is clearly seen that the top gives a blue flame indicating that the fuel gas has been efficiently burnt. When the burner is defective the flame tends to be yellowish, because many carbon particles are incandescent and finally escape as smoke or soot. In a candle the objective is not to produce too much heat but lot of light. Significant part of the flame glows in a yellowish orange colour. The top blue part is almost invisible. In a hurricane lamp we get a sooty colour till the chimney is put down ensuring an organised supply of air from the bottom. Then we get the bright orange flame we desire. Your question has a deeper significance. The analysis of colours or wavelengths of light emitted by stars allows us to determine the composition and temperature of the region from where the radiation is being emitted. Indeed, it is through using this method that we know the constitution of the Sun and stars. The physics involved in this was first worked out by the famous Indian scientist Dr Meghnad
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AFTER 12 years of extensive research scientists at Moteur Development International (MDI), France, have developed pollution-free engines and cars powered by compressed air. According to Guy Negre, the inventor of MDI Air Car, the prototype of the car has already been tested in real life conditions of traffic in the Brignoles, France. These tests have confirmed the sound basis of using air as fuel for city vehicles.
In such engines, the compressed air from the tank is fed through an injector to the cylinder or chamber, where the air expands and pushes down the pistons. The pistons give movement to the crankshaft, which gives power to the vehicle.
Car body: The body of MDI car is made of fibre and injected foam. The chassis of the car is a structure of welded steel tubes. The engine is fitted under the floor at the rear of the car. The use of fibre makes the car lighter and safer. It has the advantage of being easily repaired and does not rust. The broken parts of fibre can also be glued together with much ease. MDI is currently looking into using hemp fibre, which is 100 per cent non-contaminating.