Correlation Tests Between Japanese Full-Scale Automotive Wind Tunnels Using the Correction Methods for Drag Coefficient

摘要

This paper describes results of the correlation tests between several full-scale automotive wind tunnels in Japan. The tests were carried out during FY 2003 by members of the working group for wind tunnel correlation test, which was organized in JSAE Vehicle Aerodynamics Research Committee. Five wind tunnels were selected, i.e., three open test section type wind tunnels and two closed ones. Four test models were selected, i.e., sedan, station wagon, minivan and hatch back car, all of which are current production models. Tests were done with EADE test conditions. Correlation formulas for drag coefficient, which are based on the previous methods by Mercker and Wiedemann and Mercker respectively for open and closed test section type wind tunnels, were used. Also considered were the differences of the boundary layer thickness between five wind tunnels. Average standard deviations of CD values for the test models were modified from 0.007 to 0.005 among three open test section type wind tunnels by using the correlation formula. As for the closed test type, CD values with the wind tunnel of a moderate cross-sectional area showed the similar result with open test section type, but those with rather small cross-sectional area deviated from ones mentioned above.