Experimental Evaluation of Baffle and Louvre Muffler Geometries on Noise Attenuation, Fuel Consumption, and Exhaust Emissions in a Spark-Ignition Engine
Bagus Anggraini, Warju, Rio Adi Trisna, Ata Syifa, Sudirman Rizky

1. Universitas Negeri Jakarta
2. Universitas Negeri Surabaya
3. PGRI Gresik

Abstract

Muffler geometry plays a critical role in controlling exhaust noise while influencing engine fuel consumption, back pressure, and exhaust emissions. This study experimentally evaluates the effects of baffle and louvre muffler configurations on noise attenuation, fuel consumption, and exhaust emissions in a Toyota Kijang 5K spark-ignition engine. Three muffler configurations were compared: the standard muffler, a redesigned baffle-type muffler, and a redesigned louvre-type muffler. Tests were conducted at engine speeds from 1000 to 5000 rpm with 500 rpm intervals under controlled operating conditions. Noise level, fuel consumption, and exhaust emissions were measured according to ISO/FDIS 5130:2006(E), SNI 7554:2010, and SNI 09-7118.1-2005, respectively. The results showed that the baffle muffler reduced noise by 0.75%, fuel consumption by 10.53%, and CO and HC emissions by 7.44% and 2.51%, respectively. The louvre muffler achieved higher noise attenuation and fuel-saving performance, reducing noise by 1.56%, fuel consumption by 12.80%, and CO and HC emissions by 7.35% and 5.83%, respectively. Overall, the louvre configuration provided the best compromise between acoustic attenuation and fuel consumption, while the baffle configuration showed slightly better CO reduction.

Keywords: baffle muffler- louvre muffler- noise attenuation- fuel consumption- exhaust emissions- spark-ignition engine.

Topic: Energy and Environmental Physics