A Time Domain Analysis Technique for Aerodynamic Wind Tunnel Model Studies

Owing to the limited storage capacity and computational power of computers in the 1980s, analyses for aerodynamic model studies, such as high-frequency base balance (HFBB) or synchronous multi-pressure sensing system (SMPSS), have been traditionally conducted in the frequency domain. As computer technology has improved and the necessity to conduct the vibration control analysis in the time domain grows, this paper investigates the feasibility of implementing analyses for aerodynamic model studies in the time domain. A series of wind tunnel tests was conducted at the CLP Power Wind/Wave Tunnel Facility, The Hong Kong University of Science and Technology to determine the wind forces exerted on a benchmarking building using the simultaneous pressure measurement technique. The base overturning moments and torque were subsequently synthesised using the measured pressure data and analysed in both time domain and frequency domain from which the base overturning moment responses and the building tip acceleration responses from both analyses were compared. In addition, a parametric study on the frequency ratio between the first and the second modes of the example building was carried out to examine its effects on the resultant responses. The base overturning moment response design envelopes obtained from both analysis approaches were also evaluated. The detailed analysis procedures of both domains and their resulting comparisons are presented in this paper.