جستجوی مقالات مرتبط با کلیدواژه "wake of elliptic cylinder" در نشریات گروه "مکانیک"

In this research, the behavior and characteristics of the wake of flow around an elliptic cylinder at zero angle of attack in the presence of a tripping wire were investigated experimentally. An aluminum elliptic cylinder with major axis, minor axis and height of 42.4 mm, 21.2 mm and 390 mm respectively, was used for this purpose. The cylinder model was examined in the test section of a blower type wind tunnel. The Reynolds numbers of the experiment based on major axis are 25700 and 51400 for 10 m/s and 20 m/s speeds, respectively. Tripping wires with the diameter of 0.5 mm, 1 mm, and 1.5 mm are placed symmetrically at both sides of the cylinder, and each are tested at angles of zero, 23.7, and 40.9 degrees with respect to the stagnation point. The drag coefficient of the smooth cylinder for both 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 decreases by 75%. In the best cases, it is also reduced by 56.9% and 65.5% for the 1 mm and the 1.5 mm wires, respectively.

In this research, the behavior and characteristics of the wake of the flow around an elliptic cylinder at zero angle of attack in the presence of a tripping wire of 1 mm diameter were investigated experimentally. An aluminum elliptic cylinder with major axis, minor axis, and height of 42.4 mm, 21.2mm, and 390 mm, respectively, was used for this purpose. The cylinder model was examined in the test section of a blower type wind tunnel. The Reynolds numbers of the experiment, based on major axis were 25700 and 51400 for 10 m/s and 20 m/s speeds, respectively. Tripping wire placed symmetrically at both sides of the cylinder, and each were tested at angles of zero, 23.7, and 40.9 degrees with respect to the stagnation point. The drag coefficient of the smooth cylinder for both of the Reynolds numbers was about 0.6. The results indicate that in the best possible case, the drag coefficient for the 1 mm wire reduces by 56.5% at angle of the 23.7 degree. In the best case, it also reduces by 8.6% for angle of the zero degree, while in the worst case, the drag coefficient for angle of 40. 9 degree increase by 20.7%.