The Sensitivity of Large Eddy Simulations to Grid Resolution in Tropical Cyclone High Wind Area Applications
The Sensitivity of Large Eddy Simulations to Grid Resolution in Tropical Cyclone High Wind Area Applications
复制标题
DOI：
10.3390/rs15153785
复制
发表时间：
2023-07
期刊：
影响因子：
--
通讯作者：
Yi Jing;Hong Wang;Ping Zhu;Yubin Li;Lei Ye;Lifeng Jiang;Anting Wang
中科院分区：
文献类型：
--
作者：
Yi Jing;Hong Wang;Ping Zhu;Yubin Li;Lei Ye;Lifeng Jiang;Anting Wang
热带气旋（TC）大风区的大涡模拟（LESs）在多大的分辨率下可能收敛的问题仍然没有答案。为了解决这个问题，在这项研究中，LESs与五个分辨率为300米，100米，60米，33米，20米，模拟台风灿都（2021）的最大风力半径附近的大风区使用天气研究与预报（WRF）模式。结果表明，对于一个有限的区域LES，模型网格分辨率可能会改变当地的湍流结构，产生显着不同的极端值的温度，湿度，和风，但它只有一个边际的影响，这些变量的中值在整个垂直列。所有的模拟都能捕捉到TC边界层中的湍流滚涡，但在不同分辨率的模拟中，滚涡的结构和强度有很大的不同。垂直速度超过10 m s−1的局部百米尺度涡旋仅在20 m分辨率的模拟中观察到，而在较粗分辨率的模拟中没有观察到。分辨率湍流动量通量和湍流动能（TKEs）的总动量通量和TKEs的比例出现时，显示出一些收敛的LES网格分辨率达到100米或更精细，这表明它是一个可接受的网格分辨率LES应用程序在TC模拟。
The question of at what resolution the large eddy simulations (LESs) of a tropical cyclone (TC) high wind area may converge largely remains unanswered. To address this issue, LESs with five resolutions of 300 m, 100 m, 60 m, 33 m, and 20 m are performed in this study to simulate a high wind area near the radius of maximum wind of Typhoon Chanthu (2021) using the Weather Research and Forecasting (WRF) model. The results show that, for a limited area LES, model grid resolution may alter the local turbulence structure to generate significantly different extreme values of temperature, moisture, and winds, but it only has a marginal impact on the median values of these variables throughout the vertical column. All simulations are able to capture the turbulent roll vortices in the TC boundary layer, but the structure and intensity of the rolls vary substantially in different resolution simulations. Local hectometer-scale eddies with vertical velocities exceeding 10 m s−1 are only observed in the 20 m resolution simulation but not in the coarser resolution simulations. The ratio of the resolved turbulent momentum fluxes and turbulent kinetic energies (TKEs) to the total momentum fluxes and TKEs appears to show some convergence of LESs when the grid resolution reaches 100 m or finer, suggesting that it is an acceptable grid resolution for LES applications in TC simulations.