摘要
在目前普遍认可及广泛应用的腔体流动自持续振荡噪声频率预测方法Rossiter半经验公式中,只给出了经验常数k的推荐值,并没有给出具体的计算方法。为此,本文采用数值模拟的方法确定k值。首先,采用LES湍流模型建立腔体自持续振荡噪声预测模型。进而,分析腔体内部监测点,得到前三阶噪声峰值频率,并与k取推荐值(0.57)的Rossiter公式预测频率进行对比,预测结果存在一定的误差。然后,通过分析腔体后缘湍流脉动压力的波数-频率谱,得到k值为0.63并代入Rossiter公式,得到前三阶噪声峰值频率并与数值模拟结果吻合较好。结果表明,利用分析湍流脉动压力的波数-频率谱确定经验常数k的方法是可行的,并且能够提高Rossiter公式预测频率的准确性。
In the semi-empirical Rossiter formula,which is currently generally recognized and widely used in self-sustained oscillation of cavity flow noise frequency prediction,only the recommended value of the empirical constant k is given,and no specific calculation method is given.Therefore,this paper uses numerical simulation to determine the value of k.First,the LES turbulence model is used to establish the cavity self-sustained oscillation noise prediction model.Furthermore,the first three-order noise peak frequency is obtained by analyzing the monitoring points inside the cavity and compared with the predicted frequency of Rossiter formula with the recommended value of k(0.57).The predicted results have certain deviation.Then,by analyzing the wavenumber-frequency spectrum of the turbulent pulsating pressure at the trailing edge of the cavity,the k value of 0.63 is obtained and substituted into the Rossiter formula.The first three-order noise peak frequency is obtained,which is in good agreement with the numerical simulation results.The results show that it is feasible to determine the empirical constant k by analyzing the wavenumber-frequency spectrum of the turbulent pulsating pressure,and it can improve the accuracy of the Rossiter formula to predict the frequency.
作者
倪小松
肖新标
刘浩楠
NI Xiaosong;XIAO Xinbiao;LIU Haonan(State Key Laboratory of Traction Power,Southwest Jiaotong University,Chengdu 610031,China)
出处
《机械》
2021年第9期1-7,共7页
Machinery
基金
国家自然科学基金(U1934203)。
