城市环境下大气流动CFD缩尺模拟方法  

CFD scaled modelling of atmospheric flow in urban environment

作　　者：潘无忌 汪新[1] 赵冰春 PAN Wuji;WANG Xin;ZHAO Bingchun(School of Civil and Transportation Engineering,Guangdong University of Technology,Guangzhou 510006,China)

机构地区：[1]广东工业大学土木与交通工程学院,广州510006

出　　处：《空气动力学学报》2020年第5期908-914,I0002,共8页Acta Aerodynamica Sinica

基　　金：国家自然科学基金(51378128);广东省自然科学基金(2015A030313498)。

摘　　要：针对当前城市微气候CFD数值模拟计算开销过大的问题,通过引入相似理论改进模型以适应现有计算平台的运行环境。基于相似理论构筑了考虑对流传热和传导传热情况下大气流动的CFD缩尺模拟方法,即通过同名相似准则相等的原则构建虚拟流动介质用于缩尺模拟的计算,从而使缩尺模拟与足尺现象之间的相似性得到保证,并构筑了相应的相似边界条件。以住宅小区为原型,分别设计出对应的足尺模型和缩尺模型进行了相似模拟比较研究。结果表明:本文发展的CFD缩尺模拟方法能够很好地保证与足尺流动现象的相似性,可以达到减小计算开销的目的。研究所提出的城市微气候CFD数值模拟新方法将有助于将相似理论发展成为大型计算机工程仿真模拟的指导性理论之一。As one of the most suitable analysis tools for urban climate research,CFD simulation technology requires huge computational overhead that a microcomputer is generally hard to provide.In order to reduce computational overhead,the scaled model was introduced into the CFD simulation of urban climate based on the similarity theory.In the proposed method,a virtual flow medium was constructed according to the equivalence of each similitude criterion number between the scaled model and its prototype,and the similar boundary conditions were also given out,thus it ensured the similarity results.The proposed method was verified and analyzed by the CFD simulation of atmospheric flow within a residential district.It is demonstrated that the CFD scaled simulation is in good agreement with the full-scale model for both flow patterns and accuracy.At the same time,the computational overhead is reduced effectively.The proposed model is not only suitable for urban atmospheric flow,but also helpful for the development of scaled simulation in other large-scale engineering applications.

关 键 词：大气流动 相似理论 相似准则 虚拟流动介质 缩尺模拟 

分 类 号：O351.2[理学—流体力学]