Development of a micro-scale CFD model to predict wind environment on mountainous terrain

The installation of an observation system on mountainous terrain is important for the observation of accurate weather information and the effective prediction of pollutant of airborne virus dispersion and mountain disaster, such as a fire or landslide. However, no Korean standard for installation of the mountain meteorological observation system exists. To determine the proper location, height and size of an observation system, a wind environment analysis under various environmental conditions should be conducted; however, field experiments have time and cost limitations. The objective of this study was to develop a micro-scale 3D Computational fluid dynamics (CFD) model to predict the wind environment on mountainous terrain. In our model, the ground surface of the CFD model was classified and designed based on a digital contour map provided by the National Geographic Information Institute (NGII) and a forest type map provided by Korea Forest Service (KFS) in order to simulate air resistance of trees from the study area. The air resistances of trees were realized as porous medium and the porosity coefficients of the trees were determined based on the previous researches. The developed 3D CFD model was validated using a distribution of wind velocity and direction data measured in mountainous terrain.