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Identification of Appropriate CFD Models for Simulating Aerosol Particle and Droplet Indoor Transport

Department of Civil, Environmental and Architectural Engineering, University of Colorado, Boulder, CO 80309-0428, USA

Zhiqiang Zhai

Department of Civil, Environmental and Architectural Engineering, University of Colorado, Boulder, CO 80309-0428, USA, John.Zhai{at}colorado.edu

Computational fluid dynamics (CFD) has been widely used to predict indoor particle and droplet transport and dispersion. CFD solves simplified conservative equations that describe the major characteristics of particle and droplet indoor movement, along with the flow governing equations. This paper reviews the principles of three prevalent CFD models for indoor particle and droplet simulation: the lazy particle model, isothermal particle model and vaporizing droplet model, with a focus on the disparities between these models. The study verifies that different particle and droplet models provide distinct simulation results in which size of particle and droplet is a critical factor. To justify proper application of these models for particles and droplets with different sizes, the paper theoretically analyzes the Lagrangian transport equations for particle and droplet and identifies two crucial time numbers — particle momentum response time and evaporation lifetime. Upon these numbers, two new indices have been introduced — Stokes number and evaporation effectiveness number, which can be used as simple criteria to guide the model selection. The case studies confirm the value of the indices and provide the rules of thumb for determining appropriate CFD models for particle and droplet indoor transport under typical room conditions.

Key Words: Computational fluid dynamics • Particle • Droplet • Indoor transport simulation

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Indoor and Built Environment, Vol. 16, No. 4, 322-330 (2007)
DOI: 10.1177/1420326X06079890


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This Article Abstract Free Full Text (Free PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Liu, X. Articles by Zhai, Z. Search for Related Content Social Bookmarking                         What's this?