Aerodynamic loads correction method based on wavelet packet transform in high-frequency force balance tests. Issue 228 (September 2022)

• Record Type: Journal Article
• Authors: Hu, Xiaoqi; Xie, Zhuangning; Zhang, Lele
• Is Part Of: Journal of wind engineering and industrial aerodynamics. Issue 228(2022)
• Publication Date: 2022-09
• Subjects: High-frequency force balance -- Wind tunnel test -- Signal distortion -- Wavelet packet transform -- Power spectral density; Wind-pressure -- Periodicals; Buildings -- Aerodynamics -- Periodicals; Pression du vent -- Périodiques; Constructions -- Aérodynamique -- Périodiques; Buildings -- Aerodynamics; Wind-pressure; Periodicals
• DOI: 10.1016/j.jweia.2022.105129
• Languages: English
• ISSNs: 0167-6105

Abstract

Abstract: High-frequency force balance (HFFB) technique is a commonly used method for acquiring wind-induced response of tall buildings in wind tunnel tests. However, the resonance buffeting of the balance-model system (BMS) results in the distortion of measured aerodynamic loads. When the signal distortion is complicated due to additional vibration modes and noise interference, the existing methods fail to obtain correction results. Thus, a new correction method based on wavelet packet transform (WPT) is proposed in this paper to address the issue. The distorted signals are decomposed by WPT, and the relationship between wavelet packet coefficients and power spectral density (PSD) estimation is established. Then, the reference line that conforms to the aerodynamic attenuation characteristics is extracted by a single-degree-of-freedom (SDOF) correction method combined with a parameter identification method. Subsequently, the wavelet packet coefficients of SDOF correction results are adjusted according to the reference line. Finally, the time history of the aerodynamic load after correction is reconstructed by inverse WPT (IWPT). The proposed method is validated by a numerical example and applied to a HFFB test. Compared with the existing methods, the proposed method can address more complex distortion scenes and extend the correction frequency range to the Nyquist frequency. Highlights: A universal correction method for the signal distortion in high-frequency force balance tests is proposed. Wavelet packet transform is introduced to adjust the power spectral density according to the aerodynamic characteristics. The proposed method can correct aerodynamic loads that are distorted by additional vibration modes and noise interference. The proposed method can extend the frequency range of correction up to the Nyquist frequency.