The most effective way to control exhaust noise is to install a muffler. But the noise reduction effect is not well. The main reasons are the unreasonable structure and the problematic processing technology. The technology problem can be improved by improving the process. The design idea of the muffler, mainly based on experience, and some design calculations are under ideal assumptions.
Among these assumptions, the biggest impact is the ignoring of airflow regeneration noise, this air will impact the muffler’s pipes, shells, partitions, and other components, and then stimulate vibration radiation noise. when the muffler structure parameters are not properly, or the structure is unreasonable, or there are problems in the processing technology, it will cause the performance of the muffler to decrease. At the same time, too high air velocity will increase the pressure loss of the muffler and cause a decrease of the muffler performance.
