TUBULAR RECTANGULAR MUFFLER Russian patent published in 2007 - IPC F01N1/00 

FIELD: mechanical engineering; noise silencing.

SUBSTANCE: according to invention, tubular rectangular noise muffler contains rectangular section housing rigidly connected with end face intake and exhaust branch pipes, sound absorber arranged between housing and perforated member, and acoustically transparent material arranged between perforated member and sound absorber. Ratio of lengths of sides of rectangular outer section of muffler housing B/H lies within range of optimum values B/H=1.0-1/5. Ratio of length of sides of rectangular inner section of muffler housing b/h lies within range of optimum values b/h=1.0-2.0. Ratio of difference of length of sides of rectangular outer and inner sections of muffler housing to its length lies within optimum range of values: (B-H/L=(b-h)/L=0.2-0.42. Ratio of lengths l of branch pipes to length L of muffler lies within optimum range of values l/L=0.051-0.104. Ratio of area of free section F to length L of muffler lies within range of optimum values: F/L=0.02-0.34.

EFFECT: increased efficiency of noise silencing.