Channel layout and shape optimization of active cooling thin-walled structures

The design research of an actively fuel-cooled scramjet combustor based on traditional analysis methods has poor versatility and a long period.The substructure method was adopted to establish the fluid solid heat multi field coupling finite element model of the active cooling channel cell，and the effectiveness of the finite element model was verified by comparing with the experimental results.The influence of the number of channels on the heat transfer performance was analyzed when the structure weight and mass flow rate were constant.The super-elliptic function was used to describe the cross-section shape of the channel，and the Kriging response surface and multi-objective genetic algorithm were combined to optimize the channel shape to minimize the average wall temperature，pressure loss and maximum stress.The results showed that：there was an appropriate number of channels to coordinate the performance indicators；the position of the channel did not affect the pressure loss，but the closer channel to the gas wall indicated the better heat transfer performance； the comprehensive performance of the channel shape close to the rectangle was better.Compared with the initial scheme，the average wall temperature and the maximum temperature were reduced by 4.9% and 7.2%，respectively，while the pressure loss was reduced by 33.6 kPa （33.4%）.Therefore，the comprehensive performance of the active cooling thin-walled structure had been improved significantly.