Experimental Investigation of wake on an elliptic cylinder in the presence of tripping wire
AbstractIn this research, the behavior and characteristics of the wake of flow in an elliptic cylinder with zero angle of attack in the presence of a tripping wire were investigated experimentally. For this purpose, the used an Aluminum cylinder with an elliptical cross section of the major and minor axis of 42.4 mm and 21.2 mm, respectively, and of the height of 390 mm. The cylinder model was examined in the test section of a blower type wind tunnel. The Reynolds numbers of the experiment for the major axis are 25700 and 51400 for 10 m/s and 20 m/s speeds, respectively. Tripping wires of the diameter of 0.5 mm, 1 mm, and 1.5 mm placed symmetrically at both sides of the cylinder, each are tested at angles of zero, 23.7, and 40.9 degrees with respect to the stagnation point. The drag coefficient for the smooth cylinder for either of the Reynolds numbers is about 0.6. The results indicate that in the best possible case, the drag coefficient for the 0.5 mm wire reduces by 75%.
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