THE ROLE OF END PLATES IN TWO DIMENSIONAL WIND TUNNEL TESTS

Abstract

End plates have been used for two-dimensional aerostatic and aerodynamic wind tunnel tests. Although it is often discussed that there exists the optimum size of end plates to create a two-dimensional air flow on testing body in wind tunnel tests, the mechanism of end plate effects is not yet made clear in detail. This paper discusses the mechanism of end plate effects from various view points by measuring drag forces, base pressure distributions, wind velocity distributions around the testing body and flow visualization by hydrogen bubble techniques for the flat plate normal to flow. It is concluded that the diameter required for the circular end plates has the relation with the wake vortex formation region and it is larger than 8 times of the testing body depth normal to flow.