消声器压力损失与气流再生噪声映射转化模型

A Mapping Conversion Model on Pressure Loss and Flow Regeneration Noise of Muffler

提出了消声器压力损失与气流再生噪声的湍动能分布转化系数,建立了二者的映射转化模型.对气流再生噪声的影响因素进行分析,气流再生噪声随进口气流速度和压力损失的增大而增大,总声功率级与压力损失呈类对数变化关系,在不同消声器和不同气流速度下,计算值和试验值相对误差分别小于6%和4%.以偏置式简单扩张消声单元为例,提出了湍动能分布转化系数,建立了映射转化模型,运用该模型进行了结构参数对气流再生噪声的影响讨论.结果表明:气流再生噪声总声功率级随着扩张腔直径的增加而增大,随着进口管直径、出口管直径的增大而减小;气流再生噪声总声功率级随着腔体长度的增大而急速增大,随着进/出口管偏置距离的增大而快速下降.

The transformation coefficient of the turbulent energy distribution was proposed in order to describe the pressure loss and flow regenerative noise of a muffler.A mapping conversion model on them was also set up to analyze the influence of air velocity,different muffler structure and pressure loss on flow regeneration noise.It is found that flow regeneration noise increases with the increase of the inlet air velocity and pressure loss.The sound power level takes nearly logarithmic changes with the pressure loss.The calculated value has errors of less than 6%and 4%compared with the experimental value under different mufflers and different flow velocities,respectively.The above transformation coefficient and the mapping conversion model were applied to a biasing simple expansion muffler unit to analyze the influence of the structure parameters on the flow regenerative noise.Results show that the total sound power level of flow regeneration increases with the increase of the expansion chamber diameter,and decreases with the increase of the inlet pipe diameter and the outlet tube diameter.As the chamber length increases,the total sound power level of flow regeneration is rapidly promoted with the increase of the offset distance of the inlet tube and outlet tube.