Evaluation of various turbulence models for the prediction of the airflow and temperature distributions in atria

In this paper the performance of various turbulence models potentially suitable for the prediction of indoor air flow and temperature distributions in an atrium space was evaluated in a systematic way. The investigation tested these models for various thermal conditions in atria of different geometrical configuration in two existing buildings using the Reynolds Averaged Navier–Stokes (RANS) modeling approach. The RANS turbulence models that were tested include the one-equation model (the Spallart–Allamaras) and two-equation models (the standard k-ɛ, RNG k-ɛ, realizable k-ɛ, standard k-ω and SST k-ω models). The radiation exchange between the surfaces of the atrium space was considered using the Discrete Transfer Radiation Model (DTRM). The resultant steady state governing equations were solved using a commercial CFD solver FLUENT. The numerical results obtained for a particular time of the day were compared with the experimental data available. Relatively good agreement between the experimental and CFD predictions was obtained for each model. However, from the results obtained, it was found that the performance of two-equation turbulence models is better than one-equation model and among the two-equation models, the SST k-ω model showed relatively better prediction capability of the indoor environment in an atrium space than k-ɛ-models.

► Six RANS turbulence models were used to simulate thermal environment in an atrium.
► Four cases of thermal conditions in an atrium were simulated.
► Numerical results obtained were compared with experimental measurements.
► Good agreement was obtained between numerical and experimental results.
► The SST-k-ω turbulence model provided comparatively better results.