Optimization of trailing edge angles of single expansion ramp nozzle based on Kriging method

Based on three-dimensional numerical simulation,different trailing edge angles of single expansion ramp nozzle(SERN)were studied under the condition of nozzle pressure ratio of 25 as the design point,and nozzle pressure ratio of 15 as the undesign point.The trailing edge angles were optimized to get a higher axial thrust coefficient under the nozzle pressure ratio of both 25 and 15 by the Kriging method.Results showed that the trailing edge angles made plume expanding better and the three-dimensional effect of fluid was enhanced.This was propitious to improve the axial thrust coefficient.What's more,within the design range,the axial thrust coefficient increased from 0.94 to 0.975,about 5% after optimization.So the optimization based on Kriging method is effective.