水力发电学报2018，Vol.37Issue(1)：40-48,9.DOI:10.11660/slfdxb.20180105
垂直坐标系对于水温分层流动模拟的影响研究
Influence of vertical coordinate systems on temperature-stratified flow simulation
摘要
Abstract
With the construction of high dam reservoirs and the appearance of high performance computers,increasingly more 3D models are used in the simulations of stratified flows in reservoirs.Influence of the vertical coordinate system on the accuracy in the simulations of small scale regions is essential to 3D modeling,but there are few previous studies on it.Based on the results of a stratified flow experiment,this study focuses on evaluation of the effects of the most commonly used Cartesian z coordinate system and the σ coordinate system on the accuracy in flow and temperature simulations.It is concluded that both systems are applicable but with different accuracy and the σ coordinate is better.Static instability and extra vortices caused by bottom step in the z coordinate exaggerate vertical diffusivity and lead to weaker velocity and vertical temperature stratification than those in the σ coordinate.Distribution of horizontal velocity shows small scale circulations near the bottom that are caused by a spurious water falling process produced numerically in the z coordinate modeling.The isothermals also show a stair-stepping trend in the z coordinate system.关键词
σ坐标系/z坐标系/温度分层流/水体跌落/等温线Key words
σ coordinate system/z coordinate system/stratified flow/water falling process/isothermal line分类
建筑与水利引用本文复制引用
胡煜,张文俊,夏建新,任华堂..垂直坐标系对于水温分层流动模拟的影响研究[J].水力发电学报,2018,37(1):40-48,9.基金项目
国家自然科学基金(51479218) （51479218）
