Research on Thrust Modelling Method of Variable Flow Ducted Engine Based on BP Neural Network

To solve the problem of steady mathematical modelling of variable flow ducted engine, a modelling method based on BP neural network is proposed. Combining numerical calculation with test data of variable flow ducted engine, the thrust database based on five key characteristic parameters, including height, Math number, angle of attack, pressure of gas generator and pressure of afterburining chamber, is obtained. Based on this database, a multilayer BP neural network model is established, and the model is checked and verified. The results show that the establised model can accurately predict the theoretical mathematical model of variable flow ducted engine, and replace complex mathematical model or largescale thrust database in some situations, which lays a foundation for the development of missile control system products of ducted engine.