Numerical simulation of drifting snow: erosion and deposition models
Numerical simulation of drifting snow: erosion and deposition models
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DOI：
10.3189/1998aog26-1-191-196
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发表时间：
1998
影响因子：
2.9
通讯作者：
M. Naaim;F. Naaim-Bouvet;H. Martínez
中科院分区：
文献类型：
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作者：
M. Naaim;F. Naaim-Bouvet;H. Martínez
早期的作品进行了分析的数值模拟。安德森和哈夫（1991年）提出了一个使用针对无粘性沙子定义的“飞溅”函数的模型。Uematsu等人（1989，1991）和Liston等人（1993，1994）的方法基于流体力学守恒定律，其中雪被空气流输送和扩散。这些模型考虑了跃移层作为边界条件。对于流动和悬架，我们采用与植松和利斯顿相同的模型。对于流量和雪面之间的质量交换，我们已经开发了一个侵蚀沉积模型，其中质量交换定义为流量湍流，阈值摩擦速度和雪浓度。我们的雪蚀模型是使用Takeuchi（1980）的现场测量结果进行校准的。通过数值模拟与风洞试验结果的对比，对带底缝的实心防雪栅迎风面和背风面的积尘情况进行了验证。数值计算结果与实验结果吻合较好。各种敏感性实验的主要结果是：背风面的积累对（u */u *t）比值非常敏感（当（u */u *t）接近1时出现，当（u */u *t）> 1.2时消失），栅栏产生的全局积累随（u */u *t）的减小而增加，颗粒对湍流的反作用使迎风面的积累略有扩大。
Earlier works on numerical modelling are analysed. Anderson and Haff (1991) proposed a model using the “splash” function which was defined for cohesionless sand. The Uematsu and others (1989, 1991) and Liston and others (1993,1994) approaches are based on fluid-mechanics conservation laws where the snow is transported and diffused by the air flow. These models consider the saltation layer as a boundary condition. For the flow, and for the suspension, we adopt the same model as that of Uematsu and Liston. For mass exchange between the flow and snow surface, we have developed an erosion–deposition model where mass exchange is defined in relation to flow turbulence, threshold-friction velocity and snow concentration. Our snow-erosion model was calibrated using Takeuchi's(1980) field measurements. The deposition model was tested by comparing numerical results with wind-tunnel ones, for sawdust-accumulation windward and leeward of a solid snow fence with a bottom gap. The numerical results obtained are close to the experimental results. The main results of the various sensitivity experiments are: the leeward accumulation is very sensitive to the ratio (u */u *t) (it appears for (u */u *t) close to 1 and disappears for (u */u *t) > 1.2), the global accumulation produced by the fence increases as (u */u *t) decreases and the back reaction of particles on turbulence extends slightly the windward accumulation.