A study of influencing factors on the particle concentration and deposition in a model room with a coupled drift flux and Eulerian deposition model
(English)Manuscript (preprint) (Other academic)
The drift flux model coupled with a unified Eulerian deposition model is presented and used to discuss how it is possible to improve the understanding of the particle transport behavior in indoor environments. The validation of the model itself is achieved by a good agreement with published experimental data. A series of simulation cases have been conducted to illustrate the influential factors (particle size and density, wall roughness, release location and duration, flow obstacle) for particle concentration-distributions and depositions. The results show that the uniformity of the concentration distribution decreases as the particle size increases from submicron (0.01 and 0.1 µm) to micron (1 -10 µm), as well as when the particle density increases from 700 to 5600 kg/m3. Also, the well-mixed assumptions seem adequate for particles with a diameter smaller than 2 µm for the studied cases. Two parameters, namely, the deposited amount and deposition fraction are introduced to illustrate the deposition effect on micro sized particles. The results indicate that the deposition effect become more predominant for particles with a diameter greater than 2 µm. In view of the particle deposition, sub-micron particles are more sensitive to the variation of surface materials (wall roughness) than micron particles. For an internal source in the room, where a release over a long duration is considered, the particle dispersion is strongly related to the release location. However, this is not the case for a short release time. By studying a simple case consisting of a room with a table, it is obvious that obstacles or furnished settings bring a complicated situation for the particle dispersion and deposition. Therefore, specific simulations are needed for each real indoor environment.
Particulate matter, Dispersion, Deposition, Indoor environments, Drift-flux model, Computational fluid dynamics.
Civil Engineering Other Civil Engineering
Research subject Materials Science and Engineering
IdentifiersURN: urn:nbn:se:kth:diva-192134OAI: oai:DiVA.org:kth-192134DiVA: diva2:958150
QC 201609072016-09-062016-09-062016-09-07Bibliographically approved