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在湍流局地平衡假设下 ,建立了齐次湍能输运方程封闭模型 (HKE) ,并在平板边界层的两种经典流动中加以检验 ,给出 HKE封闭下的流速、湍流动能和湍流混合系数剖面的形式解。结果表明 ,HKE可以避免在流速剪切为零时的无湍流混合问题 ,其解与 L aufer湍流实验吻合 ,因而HKE模型比混合长理论有更合理的内涵。文中还给出 HKE封闭的浅海动力学模型 ,以湍应力和水位梯度力的平衡为运动的基本受力平衡 ,进行了模型的量阶分析和运动分析 :当阻尼频率和运动频率同量阶时 ,惯性运动不可忽略 ;在潮振荡占优的浅海中 ,对流非线性相对于惯性运动为小量 ;当阻尼频率足够大时 ,科氏力项相对于湍应力也可能为小量。
Under the premise of local equilibrium of turbulence, a closed-form model of homogeneous transport turbulence equation (HKE) is established and tested in two classical flows in the slab boundary layer. The flow rate, turbulent kinetic energy and turbulent mixing Form Solution of Coefficient Cross Section. The results show that HKE can avoid turbulent mixing problems when the shear rate is zero and its solution agrees well with the L aufer turbulence experiment. Therefore, the HKE model has more reasonable connotations than the mixed-length theory. In the paper, the closed-sea dynamic model of HKE is also given. Based on the balance of turbulence stress and water level gradient force as the basic force balance of the movement, the magnitude analysis and the motion analysis of the model are carried out. When the damping frequency and the movement frequency are the same order , The inertial movement can not be neglected. In the shallow sea dominated by the tidal oscillations, the convective nonlinearity is small relative to the inertial movement. When the damping frequency is large enough, the Coriolis force may be small relative to the turbulent stress.