Computational modelling the equilibrium atmospheric boundary layer using optimal body force terms within the near-ground zone
Reproducing the neutral equilibrium atmospheric boundary layer(ABL)in numerical wind tunnel is one of the fundamental problems of computational wind engineering.Several proper derived inflow conditions have been proposed to keep all the key characteristics of wind flow,such as velocity,turbulent kinetic energy,and dissipation rate in k-ω models or specific dissipation rate in k-ω models,which are unchanged along the longitudinal direction of barrier free computational domain.However,these additional treatments,such as imperative bottom and top boundary conditions,modification of the empirical constants in turbulence models or appended source terms within the whole domain are inconsistent with the physics of ABL over rough surface.In this paper,source terms for velocity,turbulent kinetic energy and specific dissipation rate ω transport equations are proposed based on SST k-ω turbulence model,which are constructed by the downstream distance,vertical height and error of corresponding flow characteristics.Then the distribution of source terms along streamwise and vertical directions are optimized by using the multi-objective genetic algorithm(GA),i.e.the non-dominated sorting GA(NSGA2).Maximum differences are selected as objective functions to assess the horizontal homogeneity of the generated ABL flow.By implementing the optimization procedure with three sets of inflow conditions,the optimum distributions of the source terms are given.The sources are added in the near-ground region instead of the whole domain and the height of control region is changed with downstream distance.The results show the feasibility of the source formations and optimization procedure,and more importantly,the ability of maintain the generated ABL along the streamwise direction.
neutral equilibrium atmospheric boundary layer SST k-ω turbulence model source term optimization genetic algorithm
Kai Xiao Ming Nie Chao Li Jinghan Wang Yiqing Xiao
Electric Power Research Institute of Guangdong Power Grid Co.,Ltd Harbin Institute of Technology,Shenzhen,China
国际会议
The 7th World Conference on Structural Control and Monitoring(7WCSCM)(第七届结构控制与监测世界大会)
青岛
英文
3442-3450
2018-07-22（万方平台首次上网日期，不代表论文的发表时间）