Computational Fluid Dynamics Simulation of Flow of Exhaled Particles From Powered-Air Purifying Respirators

• DOI: 10.1115/detc2019-97826
• Publication Date: 2019-11-25T20:32:28Z
• Authors: Susan S. Xu; Zhipeng Lei; Ziqing Zhuang; Michael Bergman
• Keywords: Respirator; Exhalation; Thermal manikin; Exhaled air; Particle (ecology)

Abstract In surgical settings, infectious particulate wound contamination is a recognized cause of post-operative infections. Powered air-purifying respirators (PAPRs) are widely used by healthcare workers personal protection against aerosols. Healthcare infection preventionists have expressed concern about the possibility that particles expelled from PAPR exhalation channels could lead to associated infections, especially in operative settings where sterile procedural technique emphasized. This study computational fluid dynamics (CFD) modeling simulate and visualize distribution exhaled wearer. CFD simulations, outward release particles, i.e., ratio particle concentration outside inside PAPR, was determined. also evaluated effect sizes, supplied air flow rates, breathing work rates on leakage. simulation for headform loose-fitting system included following four main steps: (1) preprocessing (establishing geometrical model wearing capturing 3D image), (2) defining mathematical system, (3) running total 24 simulations with three workloads two supplied-air (4 × 3 2 = 24) applied digital (4) post-processing results visually display determine compared inside. We assume there no ambient particle, only existed. The showed were influenced workloads, rates. found leakage wearers approximately 9% size 0.1 1 μm at light 205 L/min which similar respiratory physiology health care worker range leaking 7.6% 49. significant impact leakage, increased as decreased, workload increased, rate decreased. our should help provide foundation future clinical studies.