To study the liquid film cooling in liquid rocket engine

a liquid film model was established. The convection heat transfer and radiative heat transfer between the core flow and the liquid film

and the convection heat transfer between the wall and the liquid film were considered to analyze the heat quantity. The mass transfer inducing the entrainment and evaporation of the liquid film was calculated. The friction force between gas-liquid interface and liquid-solid interface was used to analyze the film flow. The model was used in the numerical simulation of flow field within a small engine with 400N thrust. The numerical simulation results were in good agreement with the test data

showing that the model is reasonable and feasible. Comparative analysis of simulation results of different radius and the length of cylinder section of the combustion chamber revealed that within a certain range

with the increase of the radius and the length of the cylinder section

the liquid film length decreased

and the chamber wall temperature increased

so the cooling effect became worse

the result can offer a reference for the liquid rocket engine design.