Hydrogen

Hydrogen as fuel in Anyoon Rotary engine

Problem with hydrogen to be used in normal IC engine is very high calorific value (kJ/kg) (3 times of gasoline), so heat will be very high. In order to get a proper combustion with optimum air/fuel ratio (34.3/1 about 2 times of A/F ratio of normal gasoline engines) In one kg of hydrogen, 55 times more molecules will be there than in gasoline. But size of the molecules is very less. (Due to this lean mixture causes erratic combustion). In order to use hydrogen as fuel we must do some modification in combustion process.

1.) By injecting water inside combustion chamber just after combustion can reduce heat of combustion without losing much of the pressure. (Pressure loss is due to high specific heat of water).

2.) Another is implementation of constant volume heat addition. Volume of enclosed gas is very low during constant volume heat addition and molecules will be close together so better faster combustion results even with lean mixture of hydrogen.

Since combustion completes in combustion chamber itself the high heat is concentrated in combustion chamber. So we can cool it very fast by injecting water into combustion chamber. Thus main problem of hydrogen to be used as a practical fuel can be rectified with both constant

volume heat addition and water injection. Injection of water also satisfies the requirement of adiabatic expansion. It also reduces equilibrium losses resulting in high efficiency. Another important thing is that the engine is Environment friendly in two ways zero emission other than water and less heat polluting (because of internal cooling).

Importance of internal cooling by water injection is that it lessens the threat of Global warming.