振动与冲击
振動與遲擊
진동여충격
JOURNAL OF VIBRATION AND SHOCK
2015年
12期
176-181
,共6页
流致振动%旋涡脱落%涡致振动%驰振
流緻振動%鏇渦脫落%渦緻振動%馳振
류치진동%선와탈락%와치진동%치진
flow-induced motion%vortex shedding%vortex-induced vibration%galloping
流致振动是自然界和工程领域中普遍存在的一种流固耦合现象,其流固耦合过程非常复杂,涉及许多科学上的难题,一直是国际前沿研究热点之一。针对不同截面形状柱体的流致振动进行数值计算,研究高雷诺数范围内(30000≤Re≤110000)柱体流致振动特性,分析柱体振幅、频率和尾迹旋涡形态。结果表明,粗糙表面圆柱和类梯形柱Ⅰ的的流致振动响应强于其他形状柱体,最大振幅达到3.5D。圆柱、方柱、三角柱和类梯形柱Ⅰ的流致振动随来流速度变化均观察到明显的涡致振动初始分支、上部分支和驰振。类梯形柱Ⅱ出现高频低幅振动,未观察到明显的振动分支。另外,柱体流致振动振幅和频率与尾迹旋涡形态紧密相关,在不同的振动分支,尾迹呈现出不同的旋涡形态。
流緻振動是自然界和工程領域中普遍存在的一種流固耦閤現象,其流固耦閤過程非常複雜,涉及許多科學上的難題,一直是國際前沿研究熱點之一。針對不同截麵形狀柱體的流緻振動進行數值計算,研究高雷諾數範圍內(30000≤Re≤110000)柱體流緻振動特性,分析柱體振幅、頻率和尾跡鏇渦形態。結果錶明,粗糙錶麵圓柱和類梯形柱Ⅰ的的流緻振動響應彊于其他形狀柱體,最大振幅達到3.5D。圓柱、方柱、三角柱和類梯形柱Ⅰ的流緻振動隨來流速度變化均觀察到明顯的渦緻振動初始分支、上部分支和馳振。類梯形柱Ⅱ齣現高頻低幅振動,未觀察到明顯的振動分支。另外,柱體流緻振動振幅和頻率與尾跡鏇渦形態緊密相關,在不同的振動分支,尾跡呈現齣不同的鏇渦形態。
류치진동시자연계화공정영역중보편존재적일충류고우합현상,기류고우합과정비상복잡,섭급허다과학상적난제,일직시국제전연연구열점지일。침대불동절면형상주체적류치진동진행수치계산,연구고뢰낙수범위내(30000≤Re≤110000)주체류치진동특성,분석주체진폭、빈솔화미적선와형태。결과표명,조조표면원주화류제형주Ⅰ적적류치진동향응강우기타형상주체,최대진폭체도3.5D。원주、방주、삼각주화류제형주Ⅰ적류치진동수래류속도변화균관찰도명현적와치진동초시분지、상부분지화치진。류제형주Ⅱ출현고빈저폭진동,미관찰도명현적진동분지。령외,주체류치진동진폭화빈솔여미적선와형태긴밀상관,재불동적진동분지,미적정현출불동적선와형태。
Flow-induced motion (FIM) is widely existing in the nature and engineering applications.The interactions between structure and flow are often very complex and the FIM is one of the research focuses in the fluid-structure interaction dynamics.In the present study,FIMof cylinders with different cross sections was numerically studied in the flow field with high Reynolds number range of 30000 ≤ Re ≤ 110000.The amplitude,frequency,and vortex patterns of each cylinder were examined.The results indicate that the amplitudes of the circular cylinder with rough surface and the quasi-trapezoid cylinderⅠare higher than others,and the maximum amplitude of 3.5 times of diameters is reached.The initial branch of VIV (vortex-induced vibration),the upper branch of VIV and galloping are correctly predicted in the oscillations of the circular cylinder,square cylinder,triangular prism,and quasi-trapezoid cylinder Ⅰ. FIMwith high frequency and small amplitude is achieved for the quasi-trapezoid cylinder Ⅱ,but no FIM branch can be observed.In addition,the vortex pattern of cylinder is closely related with the amplitude and frequecy responses,and the vortex pattern is stable when the cylinder is in one branch.