A Method for Predicting Interior Ballistic Performance Based on LSTM Network
Zero-dimensional internal ballistic analysis is a commonly used internal ballistic performance analysis method with simple calculation and high efficiency,and has a good performance in the study of internal ballistic performance.However,it often adopts the method of treating throat diameter change as linear ablation to simplify the throat area.A large number of ana-lyses and tests show that throat diameter ablation is not linear,and throat liner ablation mainly occurs in the middle and late stages of engine operation.Therefore,a prediction method of internal trajectory performance based on genetic algorithm and LSTM neural network is proposed in this paper.Firstly,genetic algorithm and zero-dimensional internal trajectory calculation e-quation are used to identify the throat diameter change curve from the pressure data obtained from the test.Then LSTM neural network is used to establish a throat diameter change prediction model to predict the throat diameter change curve of the engine.On this basis,the ballistic performance in the working section is predicted.The method is verified by a real case.The mean square error between the predicted curve and the actual curve is0.118 MPa,and the relative error is1.35%.The predicted results verify that the method can accurately predict the pressure change curve of solid rocket motor.