DETERMINATION OF DRAG COEFFICIENTS OF VARIOUS AUTOMOBILE MODELS IN A LOW SPEED WIND TUNNEL


Icingur Y., SOLMAZ H.

JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY, vol.26, no.2, pp.454-459, 2011 (SCI-Expanded) identifier identifier

Abstract

Wind tunnel tests are used to determine aerodynamic characteristics of road vehicles. Between model and prototype to match Reynolds number its necessary to use high speed wind tunnel or larger models. This is an important factor that increasing costs. Reynolds number independence can be used to determine aerodynamic characteristics with low speed wind tunnel and smaller models. In this study 1/24 scale three car's drag coefficient were trying to determine with utilizing the Reynolds number independence. Tests were carried out in a wind tunnel which free flow velocity is 28 m/s. As a result of the tests, it has been seen that the Reynolds number independence can not be used for all models. According to test results, the drag coefficients of BMW X5 E53, Alfa Romeo 156 and Wolksvagen New Beetle were found with 14 %, 12.5 %, 7.8 % error, respectively.