Considering empirical feature and casualness in the design for engine pipelines

the support was simplified as translation-constrained elastic spring element

the lengths between every two supports were defined as supports' positions

and the finite element method (FEM) and the discrete sampling method were applied to the dynamic sensitivity analysis of engine pipeline structure.Compared with other structure parameters

the numerical results demonstrate that some supports' positions play more important roles for complex piping.The effect of supports' amount and stiffness on the fundamental frequency and random vibration responses was discussed.The position optimizations of complex pipelines' supports were implemented to maximize difference between fundamental frequency and external excitation frequency

and minimize the random vibration standard deviation by penalty function method.