SYNCHRONOUS TONE VENTILATION NOISE IN AUTOMOTIVE ALTERNATORS

Automotive alternator noise is produced by three generalized source types; ventilation airflow, rotating mechanical components, and unsteady magnetic forces. At some frequencies, the noise spectrum is dominated by discrete ventilation tones which are integer multiples of the shaft rotational frequency. These synchronous tones are attributable to rotor blade-passage effects and rotorstator interaction. An experimental study was conducted to identify and characterize the source mechanisms associated with synchronous ventilation tones. Using sound intensity scans, the rotor and stator features which contribute to tone generation were identified. The relationships between alternator geometry and tone generation were confirmed by re-testing a modified alternator and by developing an analytical model of rotor-stator interaction.

• Corporate Authors:

  Noise Control Foundation

  P.O. Box 2469 Arlington Branch
  Poughkeepsie, NY  United States  12603
• Authors:
  • Frederick, D M
  • Lauchle, G C
• Conference:
  • Proceedings of NOISE-CON 94. Progress in Noise Control for Industry
  • Location: Fort Lauderdale, FL
  • Date: 1994-5-1 to 1994-5-4
• Publication Date: 1994-5

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 139-144

Subject/Index Terms

• TRT Terms: Alternators; Engines; Mechanical vibration; Motor vehicles; Noise; Rotor blades; Shafts (Machinery); Synchronous motors
• Old TRIS Terms: Engine noise; Vehicle noise
• Subject Areas: Environment; Highways; Vehicles and Equipment; I90: Vehicles;

Filing Info

• Accession Number: 00662995
• Record Type: Publication
• Files: TRIS
• Created Date: Jul 25 1994 12:00AM