Effects of Gas Radiation on the Thermal Characteristics of Regeneratively Cooled Rocket Engines

Abstract

This paper studies the effects of radiative heat transfer on the thermal characteristics of regeneratively cooled rocket engines. A conjugated radiative, conductive and convective model is used to analyze the effects of radiative heat transfer in two regeneratively cooled rocket engines. One engine has liquid hydrogen and liquid oxygen as the propellant and liquid hydrogen as the coolant. The other engine has RP1 (a hydrocarbon fuel) and liquid oxygen as the propellant and liquid oxygen as the coolant. It is shown that gas radiation has some effect on the wall temperature of the LH2-LO2 engine and a small effect on its coolant flow characteristics. For the RP1-LO2 engine, however, gas radiation significantly increases the coolant pressure drop, temperature and Mach number. It is also shown that radiation effects must be addressed in cooling channel design, so that wall temperatures and cryogenic coolant flow temperature/pressure are at suitable levels.