中文摘要：

下垫面的复杂性一直是数值模拟所面对的主要难题之一，尼其当复杂地形和建筑物同时存在时，问题变得极其困难，几乎已有的任何单一模式都难以很好模拟出复杂地形上建筑物周边的风场精细结构。为解决这一问题，提出利用中尺度模式RAMS与CFD模式FLUENT耦合的方法，利用RAMS的模拟结果驱动FLUENT进行复杂地形上建筑物周边风环境的精细模拟。数值模拟试验以“鹦鹉”台风登陆期间的香港国际机场为研究对象，模拟了强风条件下机场周边的风场精细结构：将模拟结果与南北两侧跑道边的6个自动站观测数据进行对比，发现风速与风向都较为一致．并较好地描述了由于建筑物所导致的机场南侧着陆航道上的横向风切变，解释了台风期间南侧跑道两架飞机着陆斟难的原因。

英文摘要：

The complexity of the underlying surface has always been one of the main challenges faced in the numerical simulation of wind fields, especially when complex terrain and buildings coexist in a simulation domain. Actually, in a case with both buildings and complex terrain, almost no existing single model can provide fine-scale wind fields in details. In order to simulate the wind environment around buildings over complex terrain, this paper presents a method of coupling a mesoscale model, RAMS, with a computational fluid dynamics （CFD） model, FLUENT, based on previous studies. In the coupling modeling system, RAMS simulation results are extracted and used to drive the FLUENT simulation runs. Taking Hong Kong International Airport as an example, the wind fields around the buildings during typhoon Nuri are simulated and analyzed. The simulated results are compared with the observed data from 6 automatic weather stations （AWSs） beside 2 runways of the airport. The comparison shows that the simulated wind direction and wind speed agree well with those from AWSs. The simulated results also describe crosswind change along the southern runway of the airport, which explains why two planes suffered hard landings during typhoon Nuri.