Measurement of Transient Heat Transfer Coefficient of In-cylinder Gas in the Hydrogen Fueled Engine with Dual Injection System

이중분사식 수소기관 연소실내 가스의 순간열전달계수의 측정

To clear the differences of heat transfer coefficient of in-cylinder gas with fuel properties, the transient heat transfer coefficient of hydrogen gas is investigated by using the hydrogen fueled engine. The measured results were also compared with those of gasoline engine and several empirical equations. Transient heat transfer coefficients were determined by measurements of unsteady heat flux and instantaneous wall temperature in the cylinder head. As the main results, it is shown that transient heat transfer coefficients have remarkable differences according to fuel properties, and it's value for hydrogen engine is twice higher than that of gasoline engine. It means that equation of heat transfer coefficient that the effect of fuel properties is considered sufficiently, is needed to analyze or simulate the gas engine performance.