运输车辆的使用性能决定于排气系统构造的完善程度:其气体阻力越小,在一定声频范围内声学特性越好,则从节约燃料及环境保护的观点来看,对运输车辆越有利。因而,专家们力图既减小气体阻力又改进声学特性,并寻找利用废气能量的方法。实现上述两点最主要的方法是改进排气系统,尤其是其基本元件——消声器的结构。众所周 The performance of a transport vehicle depends on how well the exhaust system is constructed: the smaller the gas resistance, the better the acoustic properties over a range of acoustic frequencies, the better the transport vehicle from the point of view of fuel economy and environmental protection. As a result, experts sought to both reduce gas resistance and improve acoustics, and to find ways to use exhaust gas energy. The most important way to achieve these two points is to improve the structure of the exhaust system, especially its basic components, the muffler. All week