THE APPLICATION OF URETHANE FOAMS FOR NOISE REDUCTION IN VEHICLES

The author describes results from research into the absorption characteristics of various thicknesses and forms of urethane foams. Tables are given showing the variation of absorption properties of open and closed cell foams of several thicknesses. Results show that a fine-celled open structure of greater than 25 mm thickness is required for good absorption; its density appears to play only a small role. Coating the flexible urethane foam with a non-porous film is shown to improve its absorption by making its impedance more close to that of air. The techniques adopted for airborne and structure-borne noise are explained. To achieve efficient noise reduction the right material must be used in the correct place and the treatment must be coherent. The author suggests that each case for noise reduction must be treated separately using the subtractive method outlined. /TRRL/

• Corporate Authors:

  Trade and Technical Press, Limited

  Crown House
  Morden, Surrey SM4 5EW,   England 
• Authors:
  • Scott, D
• Publication Date: 1976-11-12

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 337-339
• Serial:
  • Noise Control and Vibration Insulation
  • Volume: 7
  • Issue Number: 9
  • Publisher: Trade and Technical Press, Limited

Subject/Index Terms

• TRT Terms: Absorption; Automobiles; Electrical impedance; Expanded materials; Foams; Mechanical impedance; Methodology; Noise control; Sound; Thickness; Urethane; Vehicles; Vibration
• Uncontrolled Terms: Decreases
• ITRD Terms: 6758: Absorption; 1243: Car; 9009: Decrease; 4502: Expanded material; 9102: Method; 6748: Sound; 5933: Thickness; 5558: Vibration
• Subject Areas: Geotechnology; Highways; Materials; Safety and Human Factors; Vehicles and Equipment;

Filing Info

• Accession Number: 00152832
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Files: ITRD, TRIS
• Created Date: Jul 2 1977 12:00AM