Aerodynamics of Road Vehicles in Tunnels - Flow Visualization Using the Laser Light Sheet Method and Its Digital Image Processing

For the past several years, construction of Japanese road network has maintained a rapid pace, but those roads, having many automotive tunnels, are affected by mountainous topography. The air pollution in tunnels by exhaust gases from cars, especially those from large-size vehicles, has become problematical in Japan.

The purpose of this paper is to clarify the flow behavior, especially wake structure behind trucks, and their aerodynamics characteristics at overtaking in road vehicle tunnels with digital image processing technique and three dimensinoal numerical analysis.