隔水管附属管控制流动的风洞和水洞实验研究

通过对附属轴向管的隔水管表面压力分布和流体动力特性进行的风洞和水洞实验测试结果的对比,验证了利用低成本风洞实验代替高成本水洞实验来考察隔水管流体动力特性及漩涡特征的可行性。与经典圆柱实验的对比验证了本实验两套测试系统的可靠性。对附加管数N 4和10两种布局的附属管进行流动控制实验的结果表明,4根和10根附属管分别作为少管数和多管数情况的代表,对于流体力的影响差异较大,但均能取得一定程度的降低升阻力和抑制漩涡脱落的效果。多管数对于来流方向的敏感性要低很多。10根管能使Cd和Cl分别获得相对于单隔水管约36%和80%的降低。附属管作为一种消除流向影响以降低流体力和控制漩涡脱落的手段,为抑制隔水管涡激振动提供了参考价值。

Wind and water tunnel experiments on flow control for a circular cylinder with axial-rod shrouds attached

Wind and water tunnel experiments on the flow control for a circular cylinder with attached axial-rod shrouds have been conducted.The results verified the feasibility of the replacement of expansive water tunnel tests with wind tunnel tests in case the investigation focuses on the fluid dynamics,vortex structure features and vortex induced vibration(VIV) suppression devices.Both of the 4 rods and 10 rods shrouds can reduce fluid forces and suppress the drag and lift coefficients,and vortex shedding.However,the 10 rods shroud is less sensitive to the inflow direction than 4 rods shroud.For the 10 rods shroud case,it is concluded that both and are less than that of the corresponding bare cylinder;and a reduction up to about 36% and 80% respectively can be obtained.The axial-rod shroud can be taken as a good manner used to control VIV in practical engineering.