Performance comparison between mixing ventilation and displacement ventilation with and without cooled ceiling

Purpose – To provide the performance comparison between the conventional mixing ventilation (MV) and the displacement ventilation (DV) with and without cooling ceiling, which can be helpful to design.Design/methodology/approach – The commercial CFD software FLUENT with RNG k‐e turbulent model was used. The CFD method was validated via comparing with the available experimental data.Findings – It was found that if properly designed, the DV system can supply better indoor air quality in the occupied zone, including better distribution in temperature field, higher ventilation efficiency, lower contaminant field and more thermal comfort compared with the MV system, because of the stratification effect of DV. And the locations of return air outlets have a great effect on the performance of the ventilation system. It was also found that the DV systems can be used to remove air contaminations more efficiently, but the temperature difference in the occupied zone in the DV system is higher than that in the MV syste...

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