%0 Journal Article %T Pressure Distribution and Aerodynamics of Circular Cylinder with Freely Rotating Fairings
圆柱附加旋转整流罩表面压力分布及气动力特性 %A GU Fei %A WANG Jia-song %A ZHAO Zhuo-mao %A QIAO Xin-qi %A
谷斐 %A 王嘉松 %A 赵卓茂 %A 乔信起 %J 实验力学 %D 2012 %I %X Previous study of flow around a cylinder with fixed fairing shows that it exhibits excellent effect on drag and lift reduction and vortex-induced vibration suppression.But fixed fairing is sensitive to flow derection.When inflow direction changes,its effect may not only be reduced but present retroaction,that is drag and lift are increased and vortex-induced vibration intensified.In present study,a rotating fairing with diameter D(40 mm) and five different shape angle α(30°,45°,60°,75° and 90° respectively) was designed,and wind tunnel test for the fairing was carried out.This fairing can freely rotate around cylinder axis.Experimental results show that the fairing may rotate around an off-axis deviated from the centerline of the wake which forms an equilibrium angle δ(on either side of wake) due to integrated effect of pressure difference along either side of fairing.Off-axis angle δ increases continuously with the increase of angle α,and reachs its maximum value 62° when α = 90°.Furthermore,it is concluded that both mean drag coefficient and root-mean-square fluctuating lift coefficient,that are largely determined by equilibrium angle,are less than that of corresponding bare cylinder and the reduction up to about 43.5% and 67.0% was obtained,respectively.In addition,for small α(α≤60°),vortex shedding frequency has a significant increase compared with bare cylinder.But for large α(α≥ 75°),the situation is almost similar to bare cylinder.The peak values of rotating fairing are much lower than that of bare cylinder,which indicates that the vortex shedding is suppressed significantly. %K freely rotating fairing %K drag reduction %K lift reduction %K vortex shedding suppression %K Vortex-induced vibration(VIV)
旋转整流罩 %K 减阻 %K 减升 %K 抑制漩涡脱落 %K 涡激振动 %U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=5D344E2AD54D14F8&jid=49067A0A0D864088C06A84AACB51A5B2&aid=B789395A54251A42A9DB12533D1CB32E&yid=99E9153A83D4CB11&vid=DB817633AA4F79B9&iid=38B194292C032A66&sid=869B6F3117981EC4&eid=09D368C679EC819B&journal_id=1001-4888&journal_name=实验力学&referenced_num=0&reference_num=0