Wind Tunnel Experiments on Reducing Separated Flow Region Around Front Ends of Vehicles on Meter-Gauge Railway Lines

Abstract

Separated flow around the front end of a 1/5-scale vehicle model in a large-scale wind tunnel was examined through flow visualization using tufts and measurement of surface pressure distribution and aerodynamic drag. Various sizes and shapes of front-end edges for the vehicle were used in the experiments. The results indicated that shapes with edges rounded as elliptic arcs effectively reduce the separated flow, and that they can be used as a design guide for the front ends of vehicles on meter-gauge railway lines. The advantage of the experiments on separated flow in the large-scale wind tunnel was clearly shown by comparing the results with those previously obtained from a small-scale wind tunnel using a 1/20-scale model.