A study on a partially-open bogie fairing to improve anti-snow performance of a high-speed train

The concept of a partially-open bogie fairing has been proposed to attenuate snow accretion on bogies as well as to reduce the aerodynamic drag for high-speed trains. Numerical simulations were performed on the EMU-320 model of Korea Train eXpress running at 320 km/h with changes in the bogie fairings using Reynolds-averaged Navier-Stokes simulations. The area of the positive pressure coefficient inside the bogie region increased as the open area became smaller. The incoming flow to the bogie region was concentrated at the front open area along the bogie regions, and the incoming streamlines did not go outside due to that the rear area was closed. They prevented a flow coming from under the train because they occupied the inside volume of the bogie region. The incoming flow from under the train was controlled to relieve the snow accretion inside the bogie regions by changing the front open area. This condition led to not only dissipated vortical structures at the bogie but also drag reduction comparable to that of the perfectly-closed bogie fairing.