反流插入管消声器压力损失的分析

An Analysis on the Pressure Drop of Reverse-flow Inserted Pipe Muffler

对经试验验证的反流插入管消声器的数值模型进行计算流体力学(CFD)仿真,以研究进、出口管与后壁面距离对其压力损失的影响规律。结果表明,进口管与后壁面距离存在一临界值,小于这个临界值时压力损失急剧升高。接着进一步研究进口边界条件、介质边界条件和尺寸参数对这一临界距离影响的仿真。发现该距离主要取决于进口管内径。最后,分析存在临界距离的原因,并给出临界距离的估算公式。

A computational fluid dynamics （CFD） simulation is conducted on the verified numerical model for reverse-flow inserted pipe muffler to investigate the effects of the distance between inlet / outlet pipe and rear wall surface on the pressure drop of muffler. The results show that the distance between inlet pipe and rear wall sur- face has a critical value. When the distance is smaller than this critical value the pressure drop will sharply in- crease. Then further simulation for studying the effects of inlet boundary condition, medium boundary condition and dimensional parameters on the critical distance reveals that the critical distance mainly depends on the inner diame- ter of inlet pipe. Finally the reason for the existence of the critical distance is analyzed with an estimation formula for the critical distance given.