Development Of Muffler Design Expert System

In nowadays, there isn't a mature method to design muffler. If you want to design a muffler with good performance, you should do a lot of repeating jobs with computing and testing. Meanwhile, with the advancing permission rule of the automobile muffler, muffler design is requiring,so it is a key problem to design a good muffler in a little time. Muffler Design Expert System with a lot of expert experience and design knowledge can shorten the period of the muffler's design and avoid of a lot of repeating jobs.From the standpoint of design, the development of the design expert system includes, muffler structure, parameters'confirming, spectrum identifying, transferring-matrix method, sub-structure and so on. Besides,something about the expression of the design knowledge, the mode of Knowledge Base and the reasoning method of knowledge are also used in the system. On the basis of the design knowledge, I design the muffler design system with Visual Basic 6.0, and also It realizes the muffler structure design, structure inquiring, knowledge management and structure improving four modules independently. It is so easy and convenient that it realizes the automated connection with the Mechanical Desktop 6.0, and it can supply the three-dimensional model directly for the CAE acoustic analysis. It is very effective to express the design knowledge with Production Rules and the knowledge base management system supplies the condition for the knowledge maintenance. Based on the knowledge expression, I use the Forward Reasoning Control Strategy in the whole system.The design member should insert some engine parameters and the exhaust spectrum first, and then the system will match with the Knowledge Base and supply you some reference structures automatically. Through comparing these structures'aerodynamic quality and attenuation performance, you can get a preferable structure. And you will get the final design result after some improve measures. At last, we proved the system's correctness through a design example. I design a exhaust muffler for the engine HH474QE. Through comparing the results between the CAE analysis and the system computing, I found their attenuation performances are in the same trend. It proved the correctness and practicability of the system. .The system realizes the muffler's structure design. and supplies a design theory basis for the muffler design. Meanwhile, the funding of the Knowledge Base and the Reasoning Mechanism in the expert system supplies an effective base for the system's future development.