The noise from diesel engines fitted to trucks and public service vehicles may be reduced in 3 ways: (1) control rapid rise of cylinder pressure upon combustion, plus reduction of mechanical noise; (2) reduce response of engine structure to vibration exciting forces of mechanical impact and combustion; (3) install engine in a soundproof box with suitable ventilation. A study of the vibration mode shapes of the crankcase and cylinder block castings of several in-line engines has shown that there are certain modifications which may be incorporated into conventional engine crankcases which will reduce the noise emitted by their surfaces, and yet allow these castings to be machined on the existing transfer line. Such modifications, combined with isolation and damping treatments applied to the sump, valve gear covers, crankshaft pulley and all other noise-emitting areas of the engine, have given noise reductions of 5 dba on the four engines treated to date.(a). /TRRL/

Media Info

  • Features: Figures; References;
  • Pagination: p. 201-215

Subject/Index Terms

Filing Info

  • Accession Number: 00137800
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • ISBN: 0853346429
  • Report/Paper Numbers: Proceeding
  • Files: ITRD, TRIS
  • Created Date: Apr 27 1981 12:00AM