消声器阻力系数CFD研究及应用

摘要

Muffler is such a device which allows air to flow through itself and can control the noise of the air flow. In this paper, the type, application and characteristics of mufflers are introduced. Mufflers must have good acoustic performances and aerodynamic performances. Resistance coefficient of the muffler reflects the extents of the air flow resistance and pressure loss. The computational fluid dynamics (CFD) method is used to calculate the resistance coefficient of the muffler. The experimental verification shows that the CFD method is feasible in muffler’s draging-coefficient calculation. Taking a forklift’s muffler as an example, the resistance coefficient is calculated by using the CFD and used to analyze the muffler’s performance;the deficiency of the original design is analyzed;and the design is improved by reducing the resistance coefficient and improving the aerodynamic performance of the muffler. This research has some application value in engineering practice.%消声器是一种允许气流通过而又能控制气流噪声的装置，本文阐述其类型、应用和特点，要求消声器有较好的声学性能和空气动力性能。消声器的阻力系数体现消声器对气流阻力和压力损失的大小。利用计算流体力学（CFD）方法计算阻力系数，并经实验验证，证明CFD计算方法在消声器阻力系数中的计算可行。以某机械厂生产的叉车消声器为例，用CFD计算其阻力系数，分析原设计中的不足，加以改进，使其阻力系数降低，提高空气动力性能。利用阻力系数来分析消声器性能，在工程实际中有一定的应用价值。