Aeroacoustics of Heavy Duty Truck Side Mirrors - An Experimental Study

Side mirrors are a known source of aerodynamically generated noise in vehicles. In this work we focus on mirrors for heavy duty trucks, they are large, often not designed with main focus on aero-acoustics and are located in a cumbersome position on the up-right A-pillar of European trucks. First the test method itself is discussed. To allow fast and cost effective design loops a bespoke vehicle, where the powertrain is separated from the cab, is developed. This vehicle can be run on a standard test track. While running the tests the wind speed is monitored, any variations are then compensated for in the post processing allowing averaging over longer time periods. For the mirror tests the door of the vehicle was especially trimmed to reduce other transmission paths into the cab than the side window. Additionally other possible aeroacoustic sources were reduced as much as practically possible. The generated wind noise was monitored with surface microphones both on the mirror (in the wake) and on the window. Additionally arrays of microphones were placed inside the cab and also accelerometers on the window. First the method is evaluated using a dummy mirror that basically is a Strouhal tone generator. Then actual mirrors were tested. It is seen that although the hydrodynamic turbulence noise dominates at the surface microphones on the window, the noise that actually is seen inside the cab is the acoustic sources generated by the separation around the mirror and A-pillar and convected at the speed of sound to the window.

• Record URL:
  • https://doi.org/10.4271/2018-01-1516
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/01487191
• Supplemental Notes:
  • Abstract reprinted with permission of SAE International.
• Authors:
  • Karlsson, Mikael
  • Larsson, Robert
  • Ågren, Torbjörn
  • Chroneer, Zenitha
• Conference:
  • 10th International Styrian Noise, Vibration & Harshness Congress: The European Automotive Noise Conference
  • Location: Graz , Austria
  • Date: 2018-6-20 to 2018-6-22
• Publication Date: 2018-6-13

Language

• English

Media Info

• Media Type: Web
• Features: References;
• Serial:
  • SAE Technical Paper
  • Publisher: Society of Automotive Engineers (SAE)
  • ISSN: 0148-7191
  • EISSN: 2688-3627
  • Serial URL: http://papers.sae.org/

Subject/Index Terms

• TRT Terms: Acoustic properties; Noise; Rearview mirrors; Test tracks; Trucks
• Uncontrolled Terms: Aeroacoustics; Side mirrors
• Subject Areas: Highways; Vehicles and Equipment;

Filing Info

• Accession Number: 01686811
• Record Type: Publication
• Source Agency: SAE International
• Report/Paper Numbers: 2018-01-1516
• Files: TRIS, SAE
• Created Date: Nov 26 2018 4:55PM