Multifield Coupling Analysis And Optimization Of Heat Dissipation In Porous Sandwich Plate

The combustion chamber of a scramjet engine is facing the harsh working conditions of violent combustion of fuel and extremely high heat generated by friction with air.At the same time,because the temperature gradient in the combustion chamber is very large,it will generate great thermal stress and seriously affect the work of the engine Performance,using low-temperature fuel as a cooling fluid to flow through the cooling channel for regenerative cooling is an effective thermal management solution.This paper abstracts and simplifies the combustion chamber of the scramjet engine.By using the ANSYS Workbench platform for multi-physics coupling analysis and optimization,the heat transfer structure is improved to achieve the purpose of enhancing structural thermal and mechanical properties and reducing structural quality.The thesis mainly carried out research work in the following aspects:（1）1)Under the condition of maintaining the original multi-channel regenerative active cooling channel,through parametric geometric modeling and multi-physics coupling simulation analysis,under the same material consumption and inlet mass flow rate,the number of different flow channels and the The influence of the flow channel position on the active cooling effect and strain deformation of the combustion chamber regeneration.On this basis,the geometry of the runner cross-section is described by the hyperelliptic equation,the Kriging proxy response surface model is combined with the MOGA multi-object genetic algorithm to optimize the shape of the active cooling runner,and the effects of each optimization variable on the optimization goal are analyzed.Iterative calculation obtains the optimal solution set,and then screens to obtain the best design plan of the cooling channel.Compared with the original design plan,the final optimized plan has a reduced by 7.62%in₈（6）and a decreased by 10.05%in(9₈（6）.The structural strength is enhanced.（2）By improving the design of the two ribs of the regenerative cooling channel,two basic lattice matrix structures of straight and staggered circular rods were established.Through multi-field coupling calculations,the lattice matrix structure was determined to improve convection.The heat transfer and mechanical properties of the structure have been greatly improved compared with the original active channel,which is an effective solution.Next,considering the self-supporting constraints,the multi-field coupling analysis results of the pyramid lattice sandwich layer with different sizes,angles and layouts under this working condition are calculated,and the best configuration is given,compared with the original active In the cooling structure,the₈（6）is reduced by 6.76%,the(9₈（6）is reduced by 8.91%,and the mass of structure is reduced by 8.15%.The thermal performance of the structure is improved.Based on this,it is proposed to design a non-uniform lattice matrix structure,which can further reduce the quality of the structure while ensuring the performance of the structure.At the same time,the application scope of the two heat transfer structures is obtained by changing the inlet mass flow.