Shorter product development cycles, densely packed engine compartments and intensified noise legislation has increased the need for accurate predictions of passenger cars Exhaust system noise at early design stages. The urgent focus on the increasing CO2 emissions and the efficiency of IC-engines as well as upcoming technologies might adversely affect the noise emission from an exhaust system, so it is becoming increasingly important to evaluate the sub system level noise emissions in an early design stage in order to predict and optimize the exhaust system performance. Engine performance and vehicle NVH characteristics are two important parameters on which the design of the exhaust system has major influence.
The reduction of exhaust noise is a very important factor in controlling the exterior and interior noise levels of vehicles, particularly to reach future target values of the pass-by noise and sound engineering for the vehicle. Therefore it's necessary to conduct a sub system level noise evaluations for accurately predicting the noise emission from complete exhaust system.
The main objective of this paper is to develop an experimental test methodology for evaluating exhaust muffler shell noise in passenger cars. A new test methodology is developed for measuring and analyzing the radiation noise, for which a customized test rig was designed and fabricated. The unique feature of the so developed methodology is that it requires very minimal resources in terms of test facility as compared to the conventional testing methods. So this methodology is particularly useful for the component suppliers who don't have to make huge investments in building the test facilities.