Aerodynamic Disturbances Encountered in Highway Passing Situations

Measurements are made of the unsteady aerodynamic forces and moments acting on a 1/ 10-scale intermediate sedan as it is passed by buses and trucks in the influence of several values of ambient crosswind. These measurements are made on the “Highway Aerodynamic Test Facility,” a high-speed moving model facility built by Developmental Sciences, Inc., under a DOT-NHTSA contract. In this study, both the metric and disturbing models are traveling at actual highway speeds (70 mph) when the measurements are made. The accuracy of this method, as well as new techniques for improving the signal-to-noise, are discussed.