Abstract
Large aerodynamic drag is given off, whenever bluff based vehicles like trucks and buses travel at high speed, because of serious wake generated behind the rear based end surface. To reduce the aerodynamic drag, we try to recover the negative pressure by induction of energetic flow into the based surface using air guided vanes installed at the rear end edge corners. From the results of wind tunnel tests for a 1/16-bus model, drag reduction of ##-##16% is successfully attained. This desirable fact is found to be due to effective induction of the under floor flow.