Numerical modelling of thermal environment in a displacement-ventilated room

摘要

It is the purpose of this paper to investigate the ability of a k-(epsilon) turbulence model to predict air flow and comfort conditions in a displacement-ventilated room. Stratification effects, re-laminarization and heat flux at walls cause difficulties when CFD (Computational Fluid Dynamics) is applied and different approaches to overcome these problems are presented. Comparative studies between ordinary versus extended turbulence models are carried out and the effect of applying different types of temperature boundary conditions is shown. The exchange of radiative energy between the surfaces of the room and the heat flux at the walls are included to complete the description. The results show promising features and it is shown how the distribution of percentage dissatisfied occupants in the room can be obtained by combining criteria of human comfort and CFD results. This offers the opportunity to point out critical ares. (au)