风吹雪数值模拟的两方程模型方法  

Two-equation model for numerical simulation on snow drifting

作　　者：周晅毅[1] 李雪峰[1,2] 顾明[1] 张艳萍[1] 

机构地区：[1]同济大学土木工程防灾国家重点实验室,上海200092 [2]上海市城市建设设计研究总院,上海200125

出　　处：《空气动力学学报》2012年第5期640-645,652,共7页Acta Aerodynamica Sinica

基　　金：中央高校基本科研业务费专项资金;中国博士后科学基金(2012M511121);科技部国家重点实验室基金(SLDRCE08-A-03)

摘　　要：采用两相流理论,根据雪颗粒的运动机理,提出了新的两方程数值模型方法,认为跃移层传输方程中的源项与壁面摩擦速度、雪层阀值摩擦速度的相对大小有关,并引入待定系数来确定源项的缩放比例。接着基于数值试验的方法开展参数分析,采用将不同参数条件下的跃移质量浓度与经验公式结果进行比较的方法来确定待定系数。为了验证该方法的适用性,对开阔场地条件下的风致积雪运动进行了模拟,并与实测数据进行了比较。结果显示,数值模拟结果与实测数据吻合较好,能够定量地重现风致积雪运动的重要特性。模拟的跃移层雪质量浓度与实测结果比较一致;而悬移雪质量浓度偏高。总质量传输率的模拟结果落在实测值范围之内。Based on the two-phase flow theory, a new method of two-equation model for numerical simu- lation on snow drifting is proposed according to the movement mechanism of snow drifting. In the saltation equation, the source item is considered to be associated with the friction velocity and threshold of friction ve- locity, and an undetermined coefficient is introduced to scale the source item. Then a series of computational test with different parameters for wind velocity and property of snow layer is conducted, and the results ofsnow concentration in saltation layer, which are obtained from the computational test, are compared with those calculated through empirical formula to determine the value of this undetermined coefficient. Snow drifting in open area is simulated using the two-equation model method, and the results are compared with results from the field tests. The comparisons show that the simulation results from the two-equation model method agree with them, which indicates that the present method can reproduce the important characteristics of wind-induced snow drifting movement. The mass concentrations in saltation layer obtained from two-equa- tion model method are consistent with those from the field tests, whereas the results of mass concentrations in suspension layer are higher when compared with data from the field tests. The total mass transport rate still falls within the range of the field tests＇ results.

关 键 词：风致积雪运动 两方程模型 雪质量浓度 质量传输率 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程]