Published on Jan 24, 2020
Everyday radios, newspapers, televisions and the internet warn us of energy exhaustion, atmospheric pollution and hostile climatic conditions. After few hundred years of industrial development, we are facing these global problems while at the same time we maintain a high standard of living. The most important problem we are faced with is whether we should continue "developing" or "die".
Coal, petroleum, natural gas, water and nuclear energy are the five main energy sources that have played important roles and have been widely used by human beings.
The United Nations Energy Organization names all of them "elementary energies", as well as "conventional energies". Electricity is merely a "second energy" derived from these sources. At present, the energy consumed all over the world almost completely relies on the supply of the five main energy sources. The consumption of petroleum constitutes approximately 60 percent of energy used from all sources, so it is the major consumer of energy.
Statistics show that, the daily consumption of petroleum all over the world today is 40 million barrels, of which about 50 percent is for automobile use. That is to say, auto petroleum constitutes about 35 percent of the whole petroleum consumption. In accordance with this calculation, daily consumption of petroleum by automobiles all over the world is over two million tonnes. At the same time as these fuels are burnt, poisonous materials such as 500 million tonnes of carbon monoxides (CO), 100 million tonnes of hydrocarbons (HC), 550 million tonnes of carbon (C), 50 million tonnes of nitrogen oxides (NOx) are emitted into the atmosphere every year, severely polluting the atmosphere. At the same time large quantities of carbon dioxide (CO2) gases, resulting from burning, have also taken the major responsibility for the "green house effect".
Atmospheric scientists now believe that carbon dioxide is responsible for about half the total "green house effect". Therefore, automobiles have to be deemed as the major energy consumer and atmosphere's contaminator. Also, this situation is fast growing with more than 50 million vehicles to be produced annually all over the world and place into the market. However, at is estimate that petroleum reserve in the globe will last for only 38 years . The situation is really very grim.
Addressing such problems is what a Green engine does or tries to do. The Green engine as it is named for the time being, is a six phase engine, which has a very low exhaust emission, higher efficiency, low vibrations etc. Apart from these features, is its uniqueness to adapt to any fuel which is also well burnt. Needless to say, if implemented will serve the purpose to a large extent.
Compared to conventional piston engines, operated on four phases, the Green engine is an actual six phase internal combustion engine with much higher expansion ratio. Thus it has six independent or separate working processes: intake, compression, mixing, combustion, power and exhaust, resulting in the high air charge rate. Satisfactory air-fuel mixing, complete burning, high combustion efficiency and full expansion. The most important characteristic is the expansion ratio being much bigger than the compression ratio.
CONSTRUCTION AND WORKING
As earlier mentioned, the Green engine is a six phase, internal combustion engine with much higher expansion ratio. The term “phase” is used instead of “stroke” because stroke is actually associated to the movement of the piston. The traveling of the piston from bottom dead centre to the top dead centre or vice versa is termed a stroke. But, in this engine pistons are absent and hence, the term “phase” is used. The six phases are: intake, compression, mixing, combustion, power and exhaust.
The engine comprises a set of vanes, a pair of rotors which houses a number of small pot-like containers. It is here, in these small containers that compression, mixing, combustion are carried out. The engine also contains two air intake ports, and a pair of fuel injectors and spark plugs. The spark plugs are connected in such a system so as to deactivate them, when a fuel which does not need sparks for ignition is used. The rotor is made of high heat resistance and low expansion rate material such as ceramic. Whereas, the metal used is an alloy of steel, aluminium and chromium.
Even though the engine is of symmetric shape, the vanes traverse an unsymmetrical or uneven boundary. This shape cannot be compromised as this a result of the path taken by the intake and exhaust air. This uneven boundary is covered by the vanes in a very unique fashion. The vanes are made in such a way that it comprises of two parts: one going inside a hollow one. At the bottom of the hollow vane is a compressive spring. On top of this spring is mounted the other part of the vane. Now, let us come to the working of the engine.
The air arrives to the engine through the direct air intake port in the absence of an air inlet pipe, throttle and inlet valves on the air intake system. A duct is provided on the sides of the vane and rotor. The duct is so shaped that when the air moves through, strong swirls generate when it gets compressed in the chamber. The air pushes the vane blades which in turn impart a proportionate rotation in the small rotor which houses the chambers. The inlet air duct ends with a very narrow opening to the chamber.
The rushing air from the duct is pushed by the blades into the small chambers in the rotor. The volume of these chambers is comparatively very small. Naturally, the compression obtained by such a procedure is very satisfactory. As earlier mentioned, the compressed air is in a swirling state, ready to be mixed with the fuel which will be injected into the chamber when it will be place before the injector by the already rotating rotor.
As soon as the chamber comes in front of the fuel injector, the injector sprays fuel into the compressed air. Because of the shape of the chamber, the fuel mixes well with the compressed air. The importance of ideal mixing leads to deletion of CO emission. And also because of the strong swirling, a centrifugal effect is exerted in the air-fuel mixture. Moreover, the rotation of the burner, makes this centrifugal effect all the more effective. Mixing phase has enough time to produce an ideal air-fuel mixture as the spark plug is positioned towards the other end of the rotor or burner.
As the chamber rotates towards the “end” of its path, it is positioned before the spark plug. A spark flies from the plug into the air-fuel mixture. Because of the mixing phase, the air-fuel mixture is denser near the spark plug, thereby, enabling lean-burning of the charge and also a uniform flame front. As soon as the whole charge is ignited, the burner rotates to position itself in front of the narrow exit.
The expanded gas rushes out of the chamber through the narrow opening, thereby pushing the name in the process. The sudden increase in volume ensures that more power is released. Or in other words, the thermal energy is fully utilized.
As the thermal energy is fully utilized, the exhaust gases bring along comparatively less heat energy. This mainly helps in the thermal efficiency of the engine. It raises the engine’s thermal efficiency and also because of the complete burning of the charge, poisonous gases like CO are absent in the exhaust emissions.
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