面向空投的青藏高原风场大涡模拟研究  

Application of Large Eddy Simulation on Qinghai-Xizang Plateau Wind for Airdrop

作　　者：鲍艳松[1] 季凌潇 李欢 陆其峰[3] 王富 BAO Yansong;JI Lingxiao;LI Huan;LU Qifeng;WANG Fu(Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration/Joint Laboratory of Meteorological Environment Satellite Engineering and Application,School of Atmospheric Physics,Nanjing University of Information Science&Technology,Nanjing 210044,Jiangsu,China;China Aerodynamics Research and Development Center,Mianyang 621000,Sichuan,China;China Meteorological Administration Earth System Modeling And Prediction Center,Beijing 100081,China)

机构地区：[1]南京信息工程大学气象灾害预报预警与评估协同创新中心/中国气象局气溶胶与云降水重点开放实验室/大气物理学院,江苏南京210044 [2]中国空气动力研究与发展中心计算空气动力研究所,四川绵阳621000 [3]中国气象局地球系统数值预报中心,北京210008

出　　处：《高原气象》2024年第2期293-302,共10页Plateau Meteorology

摘　　要：青藏高原地形复杂且气候恶劣,对高原空投伞降和航空安全是巨大的挑战;本文基于数值模拟方法,研究一套适用于高原复杂地形的风场精确模拟方法。本研究首先基于WRF(Weather Research and Forecasting)模式的大涡模拟LES(Large Eddy Simulation)方案,研究青藏高原大涡模拟方法,构建一套降尺度至40 m水平分辨率的WRF-LES系统。然后,基于青藏高原大风个例,通过敏感性试验研究,评估LES方案和地形高程数据对风场模拟影响。其外,对LES方案的标准亚格子湍流应力模型中参数进行分析,得到青藏高原风场模拟的最优方案组。最后,进行批量试验,检验该方案对高原风场模拟的适用性。试验结果表明:(1)40 m分辨率的WRF-LES系统可模拟得到更精细和准确的风场信息,模拟风速平均绝对误差MAE(Mean Absolute Error)较ACM2方案减小1.4 m·s^(-1)且均方根误差RMSE(Root Mean Square Error)减小1.81 m·s^(-1);(2)高精度地形资料ASTER的接入可以改善模式对风场模拟的效果,各项误差较模式默认地形模拟结果均存在约0.2 m·s^(-1)的改善;(3)LES方案采用基于1.5阶湍流动能方案且常数项系数为0.1时模拟效果最佳,MAE为1.56 m·s^(-1)且RMSE为2.06 m·s^(-1)。批量试验验证了大涡模拟方案对于青藏高原边界层风场模拟具有较强的适用性,40 m分辨率区域风场模拟效果明显优于中尺度模拟效果,可为高原空投伞降提供准确的风场信息。The Qinghai-Xizang Plateau has complex terrain and climate,which is a great challenge to the airdrop parachute landing and aviation safety.This research focuses on Qinghai-Xizang Plateau wind field simulation in boundary layer based on numerical calculation method.Firstly,the study built a WRF-LES system and scaled down to 40 m horizontal resolution based on the large eddy simulation(LES)scheme of WRF(Weather Research and Forecasting)model,and undertook the application study of large eddy simulation on the Qinghai-Xizang Plateau.Based on a strong wind case over the Qinghai-Xizang Plateau,the impacts of LES scheme and terrain elevation data on wind field simulation were evaluated through sensitivity tests.Then,the parameters in the standard sub-grid turbulent stress models of LES scheme were analyzed,and the optimal schemes for wind field simulation on the Qinghai-Xizang Plateau was obtained.Finally,a batch test was conducted to verify the applicability of the optimal schemes to the Qinghai-Xizang Plateau wind field simulation.The test results show that the WRF-LES system with a resolution of 40 m can simulate more precise and accurate wind field information,and the MAE(Mean Absolute Error)of simulated wind speed is reduced by 1.4 m·s^(-1)and the RMSE(Root Mean Square Error)is reduced by 1.81 m·s^(-1)compared with the ACM2 scheme;The high-precision ASTER terrain data can also improve the effect of wind field simulation,and the error is approximately deduced by 0.2 m·s^(-1);The LES scheme that use 1.5-order turbulent flow energy scheme and set parameter coefficient 0.1 has the best simulation result,and the MAE is 1.56 m·s^(-1)and RMSE is 2.06 m·s^(-1);The batch test verifies that the large eddy simulation scheme is fit for the wind simulation on the Qinghai-Xizang Plateau,and the wind field simulation results in the 40 m resolution is significantly better than in the mesoscale resolution.The result shows that WRF-LES system can provide accurate wind field information for the parachute landing on the plateau.

关 键 词：青藏高原 大涡模拟 空投伞降 

分 类 号：P457.5[天文地球—大气科学及气象学]