Afterburning effect on thermal environment of four-engine liquid rockets at different altitudes

The liquid rocket propellant burns inadequately in the combustion chamber; therefore, exhaust gas reacts with oxygen and heat that was generated, which turn affects thermal environment. By using finite-rate chemical kinetics discrete ordinates method, calculation model for four-engine flowfield is established, numerically investigates afterburning effect on environment of engine plume under different altitudes. results show reactions have little influence Mach number flow, difference between peak temperatures reacting non-reacting flows less than 5%. However, a significant increase temperature mixing layer can be found, reduces increases flight altitude. At same altitude, increment flow far-field region higher near-field region. Moreover, as altitude from 15 to 35 km, base flux caused by vary 9.4% 2.7%. provide theoretical basis designing protection systems multi-engine rockets.