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Development of a muffler for control of noise pollution in a diesel engine

Abstract The present work aims at controlling the noise level of a diesel engine by developing an exhaust muffler for the same, since exhaust noise is the single largest contributor to the overall noise from the engine. The TATA 1210 six-cylinder diesel engine was considered for test purposes. A simulated design, developed by Ricardo with the application of the engine performance simulation program WAVE, was taken up, and this was modified in certain aspects to suit the engine under consideration. The muffler was fabricated and data were recorded for evaluation of the acoustic performance as well as the engine performance and for purposes of comparison with the existing muffler as well as with the open-ended exhaust system. The new muffler was found to be superior to the existing one in terms of both acoustic performance and engine performance. With the new muffler, the maximum noise reduction obtained was 19.3 dB(A) and the maximum brake thermal efficiency obtained was 39 per cent, while with the existing muffler the corresponding values were 14.5 dB(A)and 37.4 per cent. The present work has thus experimentally shown that results from WAVE can be modified and applied to an alternative design.