What is the internal structure of an exhaust pipe muffler?

[OJesse]

The exhaust pipe muffler generally consists of several parts, including the exhaust pipe, connecting sleeve, muffler cylinder, and cylinder core. Below is a detailed introduction to the internal structure of the exhaust pipe muffler: 1. Connecting sleeve: Equipped with an oil-impregnated asbestos sealing ring to prevent air leakage at the interface between the exhaust pipe and the muffler cylinder. 2. Muffler cylinder: The muffler cylinder is welded with 7 partition plates, dividing it into 8 muffler chambers (seven expansion chambers and one resonance chamber). The cylinder core features inverted triangular flow guide grooves and numerous small holes. When high-temperature exhaust gas from the engine enters the muffler at high speed through the exhaust pipe, the cross-sectional area of the muffler cylinder gradually increases, allowing the gas flow to expand and its velocity to decrease, thereby attenuating strong pulsating noise. As the gas flow continues through each expansion chamber, it is forced to pass through the throttling holes on the partition plates and the cylinder core due to the obstruction of the partition plates. This causes the gas flow to be suddenly compressed, split into numerous fine streams, and then suddenly expanded again. Through such repeated abrupt changes, the sound energy is greatly attenuated, effectively reducing exhaust noise.