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Updated: Jul 12, 2026
09:39
A Microfluidic Model of Biomimetically Breathing Pulmonary Acinar Airways
Published on: May 9, 2016
Air movement around a worker in a low-speed flow field
A E Johnson1, B Fletcher, C J Saunders
1Health and Safety Laboratory, Sheffield, UK.
The Annals of Occupational Hygiene
|February 1, 1996
Summary
Understanding airflow around workers is crucial for safety. A heated, 3D, non-breathing manikin accurately simulates human airflow in low-speed environments for testing and exposure assessments.
Area of Science:
- Occupational hygiene
- Fluid dynamics
- Industrial safety
Background:
- Accurate simulation of airflow around workers is essential for evaluating containment systems, personal dust samplers, local exhaust ventilation (LEV) effectiveness, and worker exposure.
- Existing manikin models may not fully replicate the complex airflow dynamics influenced by human body heat and respiration.
Purpose of the Study:
- To investigate and compare airflow patterns around different manikin types and a human subject in low-speed airflow.
- To determine the optimal manikin design for representative airflow measurements in occupational settings.
Main Methods:
- Utilized laser Doppler anemometry to measure velocity vectors around the torsos of heated and unheated 2D and 3D manikins, and a breathing manikin.
- Compared manikin-generated airflow patterns with those measured around a human subject under identical low-speed airflow conditions.
Main Results:
- Distinct airflow patterns were observed between heated and unheated manikins.
- A heated, three-dimensional manikin demonstrated the most comparable results to airflow around a human.
- An unheated, breathing manikin provided unrepresentative airflow data, failing to simulate real-world conditions.
Conclusions:
- A heated, rounded, three-dimensional, non-breathing, and clothed manikin is recommended for accurate airflow simulation in low-speed environments.
- This manikin design will improve the reliability of containment testing, dust sampling, LEV assessment, and worker exposure measurements.
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