数值模拟气流特征和砾石几何参数对床面空气动力学粗糙度的影响     

王晓  张伟民 《中国沙漠》2014,34(4):943-948

本文应用流体计算软件FLUENT6.3,采用非结构化网格划分技术模拟了气流特征和砾石几何参数对床面空气动力学粗糙度的影响。结果表明：空气动力学粗糙度（z₀）与风速（u）、摩阻速度（u_*）之间存在定量关系：z₀=a exp（bu/u_*）。砾石高度对空气动力学粗糙度的影响显著优于砾石直径,空气动力学粗糙度随砾石密度的变化比较复杂,先增加后减小。FLUENT在模拟风洞砾石床面动力学过程中的成功应用,是我们在研究方法上的一次有益尝试。  相似文献   

Flow around a partly buried cylinder in a steady current     

Figen Hatipoglu  Ilhan Avci 《Ocean Engineering》2003,30(2):239-249

The flow around a cylinder, surface mounted or partly buried has been examined at Reynolds number of 1.3×10⁴ and 2.6×10⁴ by using the flow visualization method in the case of steady current. The lengths of the upstream and downstream separation regions were determined and the characteristics of the flow area were discussed for the cylinder having different burial depth to the diameter ratio (G/D). For comparsion, some numerical results obtained from the application of the FLUENT, computational fluid dynamics (CFD) software package have also been presented. Both experimental and numerical results indicated that the lengths of the separation regions near the upstream and downstream of the cylinder decreased with the increasing burial ratio (G/D=0, 0.20, 0.50). The results have significant implications both for the illustration of the potential for using CFD software and highlighting the need for data of two dimensional flow around the buried cylinder.  相似文献   

带胸墙斜坡堤越浪量的数值试验研究     

王键  孙大鹏  吴浩 《海洋工程》2018,36(4):138-146

采用黏性流体的连续性方程、雷诺时均N-S方程作为基本控制方程,RNG k-ε模型模拟湍流效应,VOF方法捕捉流体自由表面,结合主动吸收式造波理论,借助FLUENT软件建立二维不规则波数值水槽。在验证数值水槽造波性能的基础上,数值模拟带胸墙斜坡堤的越浪,并将数值计算的平均越浪量与已有物模试验值进行对比,两者趋势一致,吻合良好;表明该数值水槽模拟不规则波作用带胸墙斜坡堤越浪的准确性。针对带胸墙斜坡堤,藉此分析了堤顶超高、斜坡坡比、坡肩宽度及坡肩高度对其平均越浪量影响的规律性,研究成果对斜坡堤工程设计具有重要的参考意义。  相似文献   

An Application of the RAMS/FLUENT System on the Multi-Scale Numerical Simulation of the Urban Surface Layer A Preliminary Study   总被引：1，自引：0，他引：1  

李磊  胡非  姜金华  程雪玲 《大气科学进展》2007,24(2):271-280

The Regional Atmospheric Modeling System （RAMS） and the computational fluid dynamics （CFD） codes known as FLUENT are combinatorially applied in a multi-scale numerical simulation of the urban surface layer （USL）. RAMS and FLUENT are combined as a multi-scale numerical modeling system, in which the RAMS simulated data are delivered to the computational model for FLUENT simulation in an offline way. Numerical simulations are performed to present and preliminarily validate the capability of the multi-scale modeling system, and the results show that the modeling system can reasonably provide information on the meteorological elements in an urban area from the urban scale to the city-block scale, especially the details of the turbulent flows within the USL.  相似文献