Abstract: To simulate the starting characteristics of turbofan engine in different atmospheric environments, particularly in plateau regions and at high or low temperature, a generalized description of engine starting mathematical model based on state space is given. The model considers the atmospheric condition, the starter and the load torque characteristics. A method for developing starting model via Support Vector Machines (SVM) is presented, and simulation techniques of starting characteristics are suggested and investigated. For a certain turbofan with given experimental data of engine starting at some temperature, the starting characteristics at other temperature are estimated by utilizing the recursive relations of the identified SVM model itself. The results show that the method can assure the estimation accuracy. It is fit for practical application.

Key words: aerospace propulsion system, turbofan, SVM, start, mathematical model, starting characteristics