INTERNAL COMBUSTION ENGINE EXHAUST MUFFLER Russian patent published in 2001 - IPC

FIELD: mechanical engineering; internal combustion engines. SUBSTANCE: proposed muffler has cylindrical housing with end face walls in which three chambers are formed by means of cross partitions, these chambers being inlet, central and outlet ones. Muffler has coaxial inlet and outlet branch pipes hydraulically connected to corresponding chambers by means of perforated sections and free cuts arranged in central chamber. Free dynamic cut of outlet branch pipe is located in node zone of second lower natural longitudinal mode of oscillations of gas volume enclosed in central chamber. Dynamic cut of inlet branch pipe is located in node zone of first lower natural longitudinal mode of oscillations of gas volume enclosed in central chamber. Summary volume of extreme chambers of muffler is equal to volume of its central chamber, and extreme chambers proper are made in form of concentric resonators tuned for suppressing resonant noise frequencies of main chamber at fourth longitudinal and second radial lower natural resonance modes of oscillations of gas volume in central chamber. EFFECT: increased acoustic efficiency of exhaust system preliminary muffler. 2 cl, 8 dwg