FUELS AND COMBUSTION
The working substance of the energy conversion device viz., prime-mover (which convert the natural resources of energy into power or electricity) is called fuel. The most common fuel is fossil fuel viz., Coal, petrol, diesel or water gas in the case of steam power plants, I.C. Engines, gas turbines, and hydro-electric power plants. Uranium 235(1U235) as fissionable and 1U238 as fertile fuel in the case of fission reactors of nuclear power plant and hydrogen as fuel in the case of fusion nuclear reactor. While fission reactor is conventional fusion reactor is supposed to be non-conventional due to its uncontrolled reaction rate; and it is believed that Russian?s have developed it but keeping the whole world silence. In the case of non-conventional power plants the fuels are according to their characteristics viz., Thermo-electric material (Bi2Te3, bismuth telluride, lead telluride etc.); thermionic materials (Na, K, Cs, W etc.); hydrogen or hydrocarbon or coal in the case of fuel-cells and further water and methane etc in the recent development of the sources of energy.
Combustion of the fuel is a must in any energy conversion device. It is defined as rapidly pro-ceeding chemical reaction with liberation of heat and light. This phenomenon incurved in the case of thermal power plants especially in I.C. engines and gas turbines. But in the case of fuel cell it is of the nature of chemical reaction i.e., transfer of ions, similarly in the case of thermo-electric generator it is conduction of electron and holes, in the case of MHD power plant it is drifting of positive and negative ion etc.