【摘要】 该文对已建立的齐次湍流动能输运方程封闭模型 (HKE)封闭的浅海动力学模型进行了检验。湍流混合强度的垂直分布会影流速剖面 ,在风海流、狭长渠道稳态风潮及渠道振荡流流场等的模拟中 ,HKE封闭均取得满意效果 ,结果表明 HKE封闭在正压浅海动力学中是有效的 ,可避免混合长理论的缺陷 ,并未过多增加计算量。振荡流的湍流粘性系数的时间分布特性是时变的 ,其变化频率为振荡频率的两倍 ,且在流速变化最大时湍流混合最强。对应于浅海潮波系统 ,平潮和停潮时局地混合最弱 ,因而最适宜水质采样 ,反之 ,涨急和落急时刻湍流混合最强。但当取湍动能的Schmidt数 σk>10时 ,湍粘性系数的振幅仅为其平均值的 15 % ,因此可以认为在 15 %误差内振荡流的粘性系数可用一个时间平均值来代表更多还原

【Abstract】 The Homogeneous K eguation Turbulent (HKE) closure coastal hydrodynamic model was applied to simulate the wind driven current, steady wind surge in a closed narrow channel, the oscillating current in an estuary and tide in a rectangular gulf. The vertical distribution of the viscosity, or the turbulent mixing intensity, has show that they are in agreement with the observations. Therefore, HKE is valid in coastal hydrodynamics. It can avoid the disadvantage of mixing length hypotheses and at the same time not too much computation is needed.Time dependent viscosity of the oscillating current is discusssed, and it is found that the frequency of viscosity variation is two times of that of current oscillating. Turbulent mixing reaches its maximum when the current gets the maximum acceleration. This means that the local mixing is the weakest at high and low water in the coastal area. But when the Schmidt number of the turbulent kinetic energy is larger than 10(σ k>10), the amplitude of the viscosity variation is only 15% of its averaged value. The viscosity of the oscillating current can be represented by its averaged value with an error within 15%.更多还原