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引入了子波变换的方法来确定检测壁湍流猝发事件的ＶＩＴＡ法的短时间平均周期Ｔ为 了确定ＶＩＴＡ法的短时间平均周期Ｔ；用子波变换对热膜测速仪测量得到的湍流边界层近壁区 域的流向脉动速度的时间序列进行了分解，分解在时域和频域同时进行，根据每一个尺度的子 波系数的模的平方在时域的积分得到壁湍流每一个尺度的脉动动能随尺度的分布，用能量最大 准则确定与壁湍流猝发事件的时间尺度对应的能量最大的尺度，该尺度也就是ＶＩＴＡ法的短 时间平均周期Ｔ。
A wavelet transform method is introduced to determine the short-time averaging period T of the VITA method for detecting wall turbulent burst events. In order to determine the short-time averaging period T of the VITA method, the wavelet transform is used to measure the turbulent boundary layer The time series of the flow velocity and the pulsation velocity in the wall region are decomposed. The decomposition is carried out in the time domain and the frequency domain at the same time. The pulsating kinetic energy at each scale of the wall turbulence is obtained according to the integral of the square of the modulus of the wavelet coefficient in each scale Scale distribution, the energy maximum criterion is used to determine the most energetic scale corresponding to the time scale of wall turbulent burst events, which is also the short-time averaging period T of the VITA method.