Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : November 08, 2021 - November 10, 2021
The flow structure around a 1/2 scale Ahmed body was investigated in a circuit-type wind tunnel by mean of the flow vector sensor (FVS), the I-type hot-wire probe and the oil film method. The FVS is a thermal flow sensor of MEMS, which is able to measure the instantaneous vector of the surface flow. The drag force of the Ahmed body decreases suddenly around a slant angle of 30°. The change of the wake structure of Ahmed body from the three-dimensional separated flow to the quasi-axisymmetric separated flow can be measured. The flow direction of mean vectors by the FVS on the rear slanted surface of Ahmed body agrees with the flow pattern by the oil film method. It is found that the fluctuation of the wall surface flow measured by FVS on the rear slanted surface of Ahmed body is correlated with the velocity fluctuation measured by the I-type hot-wire probe in the its wake.