Quieting of Continuous Miner Scrubber Fan Noise

Details

• Personal Author:
  Burdisso R ; Englerth T ; Ravetta P ; Schwartz K
• Description:
  In the mining industry, Noise Induced Hearing Loss (NIHL) affects 90% of miners by age 50 [Camargo et al., 2008]. This is a consequence of exposure to noise above the Permissible Exposure Level (PEL) or Recommended Exposure Limit (REL) as defined by NIOSH, i.e. a dose of 100% or an 8 hour time weighted average of 90 dBA sound pressure level at the miner's ear. In the particular case of Continuous Miners (CMs), NIOSH [3] estimates that up to 86% of the CM operators are exposed to levels above the PEL. Also, excessive noise levels affect communication inside mines and create a hazard when operators cannot hear alarms. Although most mining related injuries and illnesses have been reduced in recent years, hearing loss is an exception. Reducing the noise from the CMs would significantly improve the working environment and therefore reduce the potential of NIHL. AVEC's approach to achieve noise reduction in the CM is to target one of the major noise sources, the scrubber fan system used to remove harmful coal dust from the air. The goal of this project is to completely redesign the fan (rotor and stator) of the CM scrubber system's for reduced noise while keeping the required performance. The approach is to use modern computation tools and technologies, including some innovative technologies utilized for designing quiet propulsors for unmanned aerial vehicles such as ducted fans. The primary objective of this design effort is to reduce noise, and maintain the duct collection performance of the scrubber fan. Whereas, current scrubber fan designs generally only consider efficiency as the main design parameter. The design for noise and aerodynamic efficiency is an approach that AVEC has successfully implemented previously in different military and commercial projects where noise is a major concern, e.g. unmanned air vehicles. A redesign of the rotor and stator pair was performed using modern tools and technologies. Significant noise reductions were made by selecting an appropriate rotor and stator blade count, increasing the spacing between the rotor and stator, reducing the stator chord length, and designing new airfoils for both the rotor and stator. In particular, the stator vanes are well designed airfoils as compared to the curved flat plate currently implemented in the CMs. Analytical/numerical studies were used at this stage for aerodynamic performance and noise predictions, i.e. no experiments or measurements. Based on these studies, the new advanced fan design produces 20 dB less noise and continues to produce the same flow rate and produce the same pressure rise (head) required for dust collection. Although, the entire 20 dB of noise reduction will not be observed due to other noise sources becoming dominant, such as the scrubber fan inflow distortion noise. These other noise sources will be addressed in the Phase II. [Description provided by NIOSH]
• Subjects:
  Hearing Loss, Noise-Induced Mining Noise Noise, Occupational Occupational Health Safety Ventilation
• Keywords:
  Continuous Mining Equipment Design Miners Mining Industry Noise Exposure Noise Induced Hearing Loss Scrubbers Ventilation Equipment
• Series:
  Grant Final Reports
• Publisher:
  National Institute for Occupational Safety and Health
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Final Grant Report
• Place as Subject:
  OSHA Region 3 ; Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  OEP - Office of Extramural Programs
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  1-52
• NIOSHTIC Number:
  nn:20056453
• NTIS Accession Number:
  PB2019-101222
• Citation:
  Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, R43-OH-010282, 2013 Dec; :1-52
• Contact Point Address:
  Kyle Schwartz, M.Sc., AVEC Inc., 3154 State St, Suite 2230, Blacksburg VA, 24060
• Email:
  kschwartz@avec-engineering.com
• Federal Fiscal Year:
  2014
• NORA Priority Area:
  Mining
• Performing Organization:
  AVEC Inc., Blacksburg, Virginia
• Peer Reviewed:
  False
• Start Date:
  20120915
• Source Full Name:
  National Institute for Occupational Safety and Health
• End Date:
  20131215
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:ca1bca09ae86013a297b4f3645ff82fd0699880afd2ce30ea2dc65cfcd8733f03d17c97e72213144f770a05487e7e3f7450bca59c27128f9dc14572958f62089
• Download URL:
  https://stacks.cdc.gov/view/cdc/218895/cdc_218895_DS1.pdf
• File Type:
  [PDF - 3.34 MB ]