Modeling of indoor particulate matter deposition to occupant typical wrinkled shirt surface

Abstract

Particle matter (PM) deposition indoors on worn garments can be influenced by the presence of wrinkles. This deposition contributes to the ‘personal cloud’ effect when occupant moves to other environments dispersing PM that reach other occupants. The aim of this work is to investigate the indoor PM deposition on occupant shirt and to compare deposition rate between a control non-wrinkled shirt and a realistic wrinkled shirt. This was achieved by developing a 3D computational fluid dynamic (CFD) model coupled with a discrete phase model (DPM) of a space conditioned by a mixed convection system and occupied by a seated thermal manikin dressed in a control or wrinkled shirt. The shirt surface wrinkles were characterized by the magnitude of their out-of-plane curvature and their overall orientation. The coupled model was experimentally validated in a climatic chamber using a thermal manikin dressed in the control shirt or the wrinkled shirt which was laser-scanned to obtain its characteristics. Good agreement was found between the measured and predicted results of flow field and PM concentrations. Results: showed that PM deposition for the wrinkled shirt increased by 42.75% compared to the control shirt for particle sizes of Chatoutsidou et al. (2015) and Lindsley et al. (2012) [1–2] μm and by 58.5% for a larger particle size bin of [7.5–10] μm. This attributed to the enhanced impaction effects witnessed at the wrinkle upslopes. Moreover, particles deposited mostly on the horizontal rather than the inclined wrinkles. Increasing particle diameter increased deposition on wrinkled shirts especially in the particle size bin of [7.5–10] μm. © 2020 Elsevier Ltd