This paper is a preliminary report of an indoor pollution case study in a complex of apartments as a part of an Indoor Pollution Management Plan (IPMP). It describes the calculation by Computational Fluid Dynamics (CFD) techniques and presents the predicted air flow, Volatile Organic Compounds (VOCs) and formaldehyde contaminant distributions in an apartment comprised of a full-scale kitchen with open access to a living room, ventilated by an exhaust hood. The CFD Code PHOENICS ® , which is based on solving the full 3-D Navier Stokes equations for turbulent flow and scalar conservation equations, was used. Major kitchen indoor pollution sources, VOCs and formaldehyde emitting materials and their emission characteristics were calculated through the use of emission factors. A typical apartment was used under case study and its detailed geometry was applied for the CFD model. To analyze the characteristics of the indoor environment, different mixing ventilation schemes (different locations of the cooker/oven and air inlets) were chosen as the parameters to investigate the indoor environment. The fields of VOCs and formaldehyde for several air inlets window positions, and ventilation parameters were calculated and compared. It was concluded that CFD methods can be used as a useful tool to assist the rational design of indoor spaces.

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This paper describes the development of a two-phase radiation model for the prediction of radiant heat attenuation in fires by water mist. It has been especially developed for incorporation in comprehensive field models of fire extinguishment by a water mist. The model predicts the opacity of the mist by summing over the absorption and scattering coefficients for each panicle size present. A novel approach is proposed to reconcile the Eulerian fonn of the radiation transport equations with the Lagrangian particle tracking procedure. The model is fast, applicable to cases where the mist is modeled following the Lagrangian concept, and it retains in evidence the physics of the problem while avoiding complex mathematics. Validation with experimental measurements has shown that the model reproduces the water mist/radiation interaction with sufficient engineering accuracy. Results also indicate that radiation is a primary mechanism in fire extinguishment. since it contributes to nearly half of the total heat removal by the droplets.

Thermal radiation, although considered an important mode of heat transfer in high temperature conditions, often is neglected in re modeling, mainly because of the complex physics involved. This study provides modelers with guidance on the engineering treatment of radiation transfer. Two widely used radiation models, the discrete transfer and the six-ux models, are reviewed and their performance is assessed in a benchmark re case. The models are compared in terms of computational ef ciency, ease of application, and predictive accuracy , and their range of validity is delineated, for single compartment re cases. The results demonstrat e that the simple six-ux model suf ces for small compartment res, up to 100 kW. For higher heat release rates, where the six-ux model breaks down, the discrete transfer provides suf cient accuracy, under certain conditions. INTROD UCTIONThermal radiation can be an important mode of heat transfer in processes involving high temperatures and for that reason the computational analysis of thermal radiation transfer in enclosure ¢re modeling is essential. Predicting possible secondary ignition, for example, because of thermal radiation, is particularly important in ¢re safety engineering. Another case is the blocking of radiant heat by a water spray or mist, as an important mechanism in ¢re extinction. In many numerical simulations of ¢re behavior, the modeling of radiative transfer often is neglected, mainly because it involves complex mathematics, high computation cost, and great uncertainty concerning the optical properties of the participating media and surfaces. Nevertheless, ignoring radiative transfer may introduce signi¢-cant errors in the overall predictions.Most of the major developments in the engineering treatment of radiative transfer have been driven by the need for accurate predictions in industrial furnaces. Consequently, there have been numerous evaluations of radiation models for furnaces. For ¢re modeling, on the other hand, very few studies have been done.

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