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下载地址： https://www.tandfonline.com/eprint/fQjUiaQPCZEGWxPTSjsQ/full

The streamwise and the spanwise velocity time series are measured from the wall to the center of the cross duct for the flow in a rectangular T-junction duct, which is similar to airflow conditions of high-speed train ventilation system. The turbulent statistical properties are reported at three streamwise locations of T-junction duct, which correspond to the upstream/downstream and the centerline of the T-junction (x/D= ± 1 and 0, respectively). Turbulence intensities, skewness and flatness factor, as well as probability density functions, have been investigated at the range of Re_τ=5400-8700. Furthermore, the multiscale properties of the flatness factor are analyzed by using orthogonal wavelet transform. It is found that the turbulent intensities remain a constant in the center region for three streamwise locations while they are weakened in the turbulent boundary layer at x/ D=1 by effect of suction. The location of the strongest intermittency is located at y/h=0.56 for x/D=-1 and 0. While at downstream of T-junction (x/D=1), the location of the strongest intermittency shifts down to y/h=0.28.  Also, t he wavelet flatness factor is more clearly distinguished the intermittency of the small-scale turbulent structure compared with the conventional flatness factor and , the obtained experimental data are fitted and used to predict the mean streamwise velocity profiles.