Wind tunnel force- balance and wake- traverse tests were carried out on 0.154- scale model cars with various degrees of streamlining to determine the significance of ground treat- ment for increasing levels of aerodynamic cleanness. The wake- traverse analysis included investigations of spanwise distributions of vortex and viscous drag. Measurements for a configuration with rolling wheels showed further reductions in wake width, relative to a comparable stationary, flat- bottom- wheels case tested over moving ground. This effect was less significant than the effect of ground motion itself.
Abstract