Compound Film Cooling Cylindrical Cumbustion Configuration Optimization And Wall Temperature Calculation

Now, the ramjet combustion temperature has increased to 2500K, the material need cooling system to endure so high temperature. This paper is to build a program which takes into account all important factors and can be used to get thermal barrier board temperature, outer wall temperature, cooling air and gas pressure and so on. By adjusting different parameters, the program can also used to optimize the cooling system and assistant ramjet combustion cooling system design.An aerodynamic and heat transfer coupling 2d model is given in the paper to simulate the heat transfer in the atmosphere, the chamber wall, the cooling air, the barrier and the gas, and to calculate the temperature contour of the chamber barrier. The model considers the variation of the viscosity and thermal conductivity when temperature varies and the nonlinear gas temperature along axial direction. For some parameters whose experimental data is deficient, just like slot mass flow coefficient and film cooling holes' flow angle, Use CFD method to study and summarize equations for applying in program. Because of the convection and radiation heat transfer between gas and solid, radiation heat transfer between different walls, the temperature calculation of gas and walls are coupled. The walls and gas be calculated alternately until the result convergent.Using this program, different cooling effective factors were studied and get some conclusions: the cooling effectiveness is almost the same when increase cooling air by add sections, increase slot height or increase holes diameter; reasonable arrangement and design of sections length, slot height and holes diameter can. effectively decrease the thermal barrier maximal temperature; thermal barrier with ribs can enhance resistance and reduce flux, can not increase cooling effectiveness; adjusting cone angle can adjust the inlet flux of cooling air channel.Based on common cooling effectiveness guideline and the specific requirement of the system, we put forward the conception of cooling system optimization degree and optimized one cooling system according the conception. For multiple parameters optimization, we gradually optimize the cooling system by adjust the main parameters first and then the secondary parameters. The result analyses show that the method was feasible.