摘要
采用相容拉格朗日-欧拉法,研究圆柱壳表面不间断振动时黏性流体的速度以及壳体的推进速度。根据黏性流体分子的黏附条件简化接触面条件,变形后的变量通过变形前各量的泰勒级数展开式近似表示。假设雷诺数Re<0.1,纳维-斯托克斯方程采用斯托克斯近似,考虑弹性圆柱壳表面发生横向振动与纵向振动。结果表明,弹性圆柱壳半径增大时,流体的速度趋近于薄板振动时的结果,纯横向振动时壳的位移方向与波的方向相反,纯纵向振动时二者方向相同,两种形式的振动均有,则方向可能相同,也可能相反。
Here, when a cylindrical shell vibrated continuously in viscous fluid, velocity of viscous fluid and the cylindrical shell's propulsion speed were studied with the united Lagrangian-Eulerian method. The contact surface conditions were simplified according to adhesion conditions of viscous fluid molecules. Variables after deformation were approximately expressed with their Taylor series expansions before deformation. When Reynolds number Re < 0.1, Navier-Stokes equations were replaced by Stokes ones to study transverse and longitudinal vibrations of the elastic cylindrical shell. The results showed that fluid velocity distribution approaches a thin plate vibration results with increase in cylindrical shell's radius; the shell's displacement direction is opposite to the wave's one during shell having transverse vibration, but their directions are the same during shell having longitudinal vibration; their directions may be the same or opposite during shell having both transverse and longitudinal vibrations.
引文
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