Radiative Heating in Combustion Chamber of Liquid Propellant Rocket Engines

抄録

The effects of radiation heat transfer in rocket engine combustion chambers are studied analytically. The fuel is hydrogen, methane or ethanol, and the oxidizer is oxygen. Radiative heat fluxes are estimated using empirical equations, and convective heat flux is estimated using flux on a flat plate, with modification of circumferential length in convergence to, or divergence from, the throat. The calculated total heat flux including radiation and convection showed reasonable agreement with the flux measured experimentally. The ratio of radiative heat flux to total flux is increased up to 30% in the cylindrical section, whereas it is less than 10% at the throat. The effect of radiation on the total amount of heat transferred to the chamber is remarkable when increasing the length of the cylindrical section and diameter, respectively. It is also made clear that the conventional estimation method of heat flux based on the pipe flow model can estimate larger heat flux in small chambers, in spite of ignoring the effects of radiation.