Wind tunnel tests on road vehicle models using a moving belt simulation of ground effect

Abstract

A moving belt simulation of ground effect is necessary for tests in wind tunnels of road vehicle models. This need has been convincingly demonstrated using $\text{1}\text{3}$ scale racing car models, $\text{1}\text{4}$ scale saloon and sports car models and small scale truck models in a 2.1 × 1.7 m wind tunnel over the last twelve years. The development of new techniques enabled measurement of forces to be made on models with wheels rotating on a moving ground. The requirement for large models to increase Reynolds number and improve the model detail led to the construction of a large 2.4 × 5.3 m moving belt rig in a new 3.5 × 2.6 m wind tunnel. In order to measure forces and pressures on road vehicle models in crosswinds, a technique using yawed models with rotating wheels on a yawed moving ground was also developed.