Impact of bogie fairing configuration on the aerodynamic performance of high-speed train under crosswind

Abstract

In this paper, the unsteady aerodynamic characteristics of a three-car grouped high-speed train (HST) with different bogie fairing configurations under the crosswind are studied using improved delayed detached eddy simulation (IDDES) at Re = 1.85 × 106. The numerical method results are validated against the previous wind tunnel experiments. There are three cases with original half-fairing configuration (HFC), non-fairing configuration (NFC) and full-fairing configuration (FFC), respectively. The numerical results show that the bogie fairing configuration has significant effects. Compared to the HFC case, the drag force coefficients of the head, middle and tail cars with NFC increase by 53.13%, 14.87% and 27.04%, and corresponding parts of the FFC case decrease by 49.98%, 24.40% and 12.41%, respectively. The FFC case can also optimize the pressure distribution on the windward and leeward sides of the HST, and the flow structure and vertex distribution around the car body are also optimized. In addition, the increasing encirclement of the fairing configurations reduces the maximum lateral flow velocity inside the bogie cavities by 70% for HFC and 50% for FFC compared to the NFC. Overall, the FFC presents better aerodynamic performance than the NFC and HFC cases under crosswind, which is recommended for the design of the HST.