CFD and wind tunnel study of the performance of a uni-directional wind catcher with heat transfer devices

Computational Fluid Dynamics (CFD) and wind tunnel analysis were conducted to investigate the performance of a uni-directional wind catcher. A detailed experimental benchmark model was created using rapid prototyping and tested in a closed-loop subsonic wind tunnel. An accurate geometrical representation of the wind tunnel test set-up was recreated in the numerical modelling. Experimental results for the indoor and external airflow, supply rate, and pressure coefficients were compared with the numerical results. Smoke visualisation experiment was also conducted to further analyse the detailed airflow structure within the wind catcher and also inside the test room. Following the successful validation of the benchmark CFD model, cylindrical Heat Transfer Devices (HTD) were integrated into the uni-directional wind catcher model to reduce the temperature of air induced into the ventilated space. The findings of the CFD study displayed that the proposed wind catcher was capable of reducing the supply temperature by up to 12K within the micro-climate depending on the outdoor air speed. However, the addition of the cylindrical HTD also reduced the air supply rates by up to 20-35%.