Identification of Key Factors Affecting the Safety Design of Aviation Piston Engine Based on Kriging-Sobol

Aiming at the safety of aviation piston engines and the complex issues of inefficient calculation by traditional safety evaluation methods, a model-based system safety analysis method based on Kriging-Sobol is proposed to research the design safety of piston engines and to identify key parameters. Depending on the characteristics of aviation piston engines involving multiple physical domains and model-based safety evaluation criteria, the Kriging model is used to enhance the computational efficiency, and a quantitative safety evaluation model is established by the concept of Sobol variance. Results show that the calculation method using the Kriging model could save 95.58% of the calculation costs; under the case in this study, the impact of injected mass per cycle on the safety of the overall engine is the greatest. The method not only improves the efficiency of identifying key factors of aviation piston engine safety evaluation and saves costs of iterations in design phase, but also compensates for the deficiency of engine safety evaluation in multiple physical domains.