剪切来流条件下的涡生振荡机理

发布时间：2018-01-01 12:21

本文关键词：剪切来流条件下的涡生振荡机理　出处：《国防科技大学学报》2016年06期 　论文类型：期刊论文

【摘要】：将指数极坐标系建立在运动的圆柱上,推导了运动坐标中剪切来流条件下,涡生振荡的涡量-流函数守恒方程、其初始和边界条件、圆柱表面的水动力表达式、圆柱振荡方程。对圆柱从静止开始振荡到发展为稳定振荡状态进行了计算和讨论,描述了脱体涡街的发展过程、升阻力相图的连续变形和漂移、圆柱振荡和平衡位置的变化过程。研究了涡生振荡终态随剪切度K的变化。结果表明:剪切来流给流场加入了背景涡,使圆柱的上涡增强、下涡减弱,流场的对称性被破坏。随着剪切度K的增大,涡街的倾斜程度增大,压力曲线的漂移量增大,由此导致升力的绝对值增大,圆柱的振幅增大且平衡位置向圆柱下侧的漂移也增大。
[Abstract]:In this paper, the exponential polar coordinate system is established on the moving cylinder, and the conservation equation of vortex-flow function, initial and boundary conditions, and hydrodynamic expressions of the cylinder surface are derived under the condition of shear flow in the motion coordinate. The oscillatory equation of cylinder is calculated and discussed from static oscillation to stable oscillation. The development process of detached vortex street and the continuous deformation and drift of phase diagram of lift resistance are described. The variation of the final state of vortex-generated oscillation with shear degree K is studied. The results show that the shear flow adds background vortex to the flow field, which enhances the upper vortex and weakens the lower vortex. The symmetry of the flow field is broken. With the increase of shear degree K, the gradient of vortex street increases, and the drift of pressure curve increases, which leads to the increase of the absolute value of lift. The amplitude of the cylinder increases and the drift of the equilibrium position to the bottom of the cylinder increases.
【作者单位】：南京理工大学瞬态物理国家重点实验室;
【基金】：国家自然科学基金资助项目(11202102) 高等学校博士学科点专项科研基金资助项目(20123219120050) 江苏省高校研究生实践创新计划资助项目(SJLX15_0185)
【分类号】：O353.4
【正文快照】： 流固耦合问题在航空航天工程、建筑工程及海洋工程等领域大量存在,如高层建筑、近海工程结构以及海底管线等,它会加剧一些复杂的固体振动,在不理想的条件下甚至可能导致结构损伤和破坏,因此对于流固耦合的研究有重要的实用价值和学术意义。最典型的问题是对于一个装置在转动底

【相似文献】