Optimization Design Of Complex Resistant Muffler Based On The Orthogonal Analysis

With the development of industry and the amelioration of human’s living conditions, environmental pollution has become a vital problem which is causing more and more serious effects on people’s daily life and work. Engineering machineries, an important component of China’s Equipment Manufacturing Industry, will surely cause environmental noise in their operating process. Exhaust noise of internal combustion engines is the primary noise resource of engineering machineries. With the enhancement of combustion motors’ quality and efficiency, exhaust noise is also growing. Exhaust muffler, as the most direct and efficiency equipment to control combustion motors’ noise, its optimal design possesses important practical values for enterprise.Among several methods about muffler performance research and structure optimal design, the artical based on the orthogonal analysis to optimize the design of the muffler with complex structure is given. By analyzing orthogonal experiment results of muffler simulation to determine whether the main parameters affect obviously on the performance of the muffler.In this paper, different types of the muffler units and their features accordingly are introduced firstly, and muffler evaluation standard and design requests are shown, then structure components and designing factors of the complex muffler are analyzed.The design procedures of orthogonal experiment and processing method of experiment result are specifically represented. The test of main structural parameters of typical and complex muffler is based on orthogonal experiment design. By analyzing the result of the tests, the influence degree and cause of structural parameters such as perforated pipe, inserting tube and the length of each chamber is investigated on aerodynamics performance and acoustic performance. Frequency characteristic features of the main structural elements of the muffler are discussed by comparing the transmission loss curves. According to the orthogonal analysis of complicated structural muffler research, orthogonal design process is applied to the design example. Based on the results, optimizing muffler structure is improved and achieved well performance.The designing procedure of orthogonal design process is concluded and applied to the orthogonal design instances. Bench test and on-board test are introduced for measuring the aerodynamics performance and acoustic performance evaluation index of muffler. The study of the resistance muffler used as the power diesel engine exhaust device in the region of engineering machinery is achieved good results. The goal of reducing excavator exhaust noise is achieved on the premise of low power loss.