Large Eddy Simulation and Hilbert Huang Transform for fluctuation pressure of high speed train

Fluctuation pressure acting on the surface of high speed trains is the main source of aerodynamic noise. Therefore, it becomes very important to research components of the fluctuation pressure for controlling the aerodynamic noise. In this paper, Large Eddy Simulation (LES) method is applied to calculate the fluctuation pressure acting on a certain type of CRH high speed train and the distribution rule of the fluctuation pressure is studied by Hilbert Huang Transform (HHT) method. Both the fluctuating part and the average part from the surface pressure are extracted by Empirical Mode Decomposition (EMD). A comparison of the distribution rules for fluctuation pressure at two different speed levels is made.