对冲孔对分流气体对冲消声单元压力损失的影响

摘要

The influence of shape and position of rushing holes on pressure loss and transmission loss of the splitstream-rushing muffler unit was analyzed.The results show that the pressure loss of the new muffler unit is the least and the transmission loss is greater,when the shape of rushing holes is rectangle and its center distance takes the averaged value (averaged value of the maximum limit and the minimum limit center distances).In other words,the new muffle unit obtains a greater overall performance.The pressure loss and transmission loss of the new-type muffler unit was computed by using numerical simulation and test methods.Moreover,the performance-comparison tests between new-type muffler unit and an original muffler was performed on a single-cylinder diesel engine.The results show that the pressure loss of the new-type muffler unit is 15.3％ lower than that of the original muffler at the inlet velocity of 30 m/s,and average insertion loss of the new-type muffler unit is 3 dB higher than that of the original muffler.The feasibility of the new-type muffler unit is then verified.%笔者分析了对冲孔形状和位置对分流气体对冲消声单元压力损失及传递损失的影响.结果表明:对冲孔的形状为矩形,对冲孔中心距取平均时(最大极限中心距和最小极限中心距的平均值),消声单元压力损失最小,传递损失较大,即具有较好的综合性能.利用数值模拟法和实测法对新型消声单元的压力损失和传递损失进行了计算,并与某型单缸柴油机原装消声器进行了性能对比试验.结果表明:入口流速为30 m/s时,新型消声单元与原装消声器相比,压力损失减小15.3％,平均插入损失增大3 dB,验证了新型消声单元原理的可行性,为该类消声单元设计理论研究及优化设计提供了参考.