摘要
目的 研究剪切流从层流向湍流转变的物理机制方法 从包含角动量守恒方程的新流体力学方程组出发,进行理论分析结果 得到了剪切流转捩过程中大尺度运动的方程和小尺度运动的方程,并对空间局部高剪切区中的小尺度运动建立了一个四波相互作用模型结论 流体大尺度运动的方程仍具有NavierStokes方程的形式,而对于局部高剪切区中的小尺度扰动,必须同时考虑流体质元的速度v(r,t)和角速度(r,t)的相互作用。
Aim To investigate the physical mechanisms of laminar turbulent transition of shear flows. Methods Theoretical analysis was made based on a new set of hydrodynamic equations including a conservation equation of angular momentum. Results Equations for large scale motion and for small scale motion were derived and a four wave interaction model for the small scale disturbances in local high shear regions was established. Conclusion For the large scale motion the Navier Stokes equation remains valid, but for the small scale motion in local high shear regions the interaction between the velocity v(r,t) and the angular velocity ω(r,t) of fluid element must be taken into consideration, which may lead to new dynamic behavior.
出处
《北京理工大学学报》
EI
CAS
CSCD
1999年第5期548-553,共6页
Transactions of Beijing Institute of Technology
