Research on the numerical fitting and optimization of the flow field of cosine-shaped mountain ranges in real mountainous terrain

Abstract

Many power facilities are constructed in mountainous areas and suffer from wind-induced disasters. A real mountainous terrain spanning 4.65 km along the Zhejiang coast was selected for analysis. The terrain model was constructed at a 1:1500 scale ratio for conducting wind tunnel test on terrain flow field measurement. Several typical cosine-shaped mountain ranges were extracted from this real mountainous terrain to model and optimize the wind speed-up ratios above the terrain. Comparisons were made between the wind speed-up ratios calculated using empirical formulas for isolated cosine-shaped mountain ranges and those derived from Chinese and American standards, against the wind tunnel test results. A detailed analysis was conducted on the impact of two types of terrain interference on calculating wind speed-up ratios. The results indicate that, due to the interference suppression effects present in real terrains, the empirical formulas and the calculated values from both Chinese and American standards generally overestimate the wind speed-up ratios. The speed-up ratio profile obtained from the empirical formula for isolated cosine-shaped mountain ranges showed similarity to the wind tunnel test results, suggesting that a single wind reduction coefficient could be applied along the profile height for correction. Wind reduction coefficients for terrain interference were provided based on the wind tunnel test data.