Computational fluid dynamics investigation of human aspiration in low velocity air: orientation effects on nose-breathing simulations

Details

• Personal Author:
  Anderson KR ; Anthony, T. Renée
• Description:
  An understanding of how particles are inhaled into the human nose is important for developing samplers that measure biologically relevant estimates of exposure in the workplace. While previous computational mouth-breathing investigations of particle aspiration have been conducted in slow moving air, nose breathing still required exploration. Computational fluid dynamics was used to estimate nasal aspiration efficiency for an inhaling humanoid form in low velocity wind speeds (0.1-0.4 m s-1). Breathing was simplified as continuous inhalation through the nose. Fluid flow and particle trajectories were simulated over seven discrete orientations relative to the oncoming wind (0, 15, 30, 60, 90, 135, 180 degrees). Sensitivities of the model simplification and methods were assessed, particularly the placement of the recessed nostril surface and the size of the nose. Simulations identified higher aspiration (13% on average) when compared to published experimental wind tunnel data. Significant differences in aspiration were identified between nose geometry, with the smaller nose aspirating an average of 8.6% more than the larger nose. Differences in fluid flow solution methods accounted for 2% average differences, on the order of methodological uncertainty. Similar trends to mouth-breathing simulations were observed including increasing aspiration efficiency with decreasing freestream velocity and decreasing aspiration with increasing rotation away from the oncoming wind. These models indicate nasal aspiration in slow moving air occurs only for particles <100 um. [Description provided by NIOSH]
• Subjects:
  Aerosols Air Movements Air Pollutants, Occupational Dust Inhalation Exposure Men Nose Occupational Health Particulate Matter Respiratory System Safety Sense Organs Women Workplace

  More +
• Keywords:
  Air-flow Airborne-particles Analytical-models Analytical-processes Author Keywords: Dust Biological-effects Breathing Dust-inhalation Dusts Dust Sampling Convention Exposure-levels Humans Inhalability Inhalable Dust Inhalants Low Velocity Mathematical-models Model Models Nasal-cavity Nose Particle-aerodynamics Samplers Sampling Simulation-methods Work-environment Workers

  More +
• ISSN:
  0003-4878
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Iowa ; OSHA Region 7
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  58
• Issue:
  7
• NIOSHTIC Number:
  nn:20044518
• Citation:
  Ann Occup Hyg 2014 Jun; 58(5):625-645
• Contact Point Address:
  T. Renée Anthony, Department of Occupational and Environmental Health, University of Iowa, 145 N. Riverside Drive, Iowa City, IA 52242
• Email:
  renee-anthony@uiowa.edu
• Federal Fiscal Year:
  2014
• Performing Organization:
  University of Iowa
• Peer Reviewed:
  True
• Start Date:
  20080601
• Source Full Name:
  Annals of Occupational Hygiene
• End Date:
  20130531
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:49804a915f6725a76c86119f91f614aaca48c3675b45d261ccc2bafa4ddab46dc0a5a617976424a2e51b4132ccc03111e5d1d476e4f6fa92f30ba9721a29ef1a
• Download URL:
  https://stacks.cdc.gov/view/cdc/200204/cdc_200204_DS1.pdf
• File Type:
  [PDF - 4.24 MB ]