Wind tunnel investigation of high-rise building aerodynamics under typhoon wind profiles featuring low-level jets

Low-Level Jets (LLJs)—rapid increases in wind speed at heights of 40∼100m commonly observed in typhoon eyewall regions—cause complex spatial variations in boundary-layer wind profiles and significantly influence the aerodynamics of tall buildings. A comprehensive evaluation of these effects is essential for the wind-resistant design of high-rise structures in typhoon-prone regions. A multi-blade device was developed to reproduce typhoon wind profiles featuring LLJs within a conventional boundary-layer wind tunnel. Wind pressure tests were conducted on a 1:200 scaled CAARC model to compare the aerodynamic effects of typhoon wind profiles (TWP) with synoptic wind profiles (SWP). The analysis covers mean and fluctuating pressure coefficients, local force coefficients, base moment coefficients, and force coefficients power spectral densities. Proper Orthogonal Decomposition (POD) was employed to identify dominant wind pressure patterns and quantify energy contributions. Results show that LLJ markedly modify surface pressure distributions and vortex shedding behavior. Under TWP, the maximum drag coefficient reached 1.427, exceeding the SWP value of 1.244 and the Chinese code limit of 1.4. POD analysis reveals that TWP alters vortex formation, suppresses vortex shedding, and reduces crosswind loads relative to SWP. These findings provide valuable insight for wind-resistant design and performance assessment of high-rise buildings in typhoon-prone aeras.