Performance Testing and Comparison of A Turbine Ventilator, A Vent Column, and Their Combination Under Thermal Buoyancy and Wind Effects

Ventilation performance of a curved-blade turbine ventilator, a straight column covered with a flathat, and a device of their combination of the same material and throat diameter of 21cm weretested on a room model of 3.0m long, 1.5m wide, and 3.0m high under simulated external windand/or internal heat source. The wind speed was from 0m/s to 3.6m/s. The heat flux was up to3KW. Air speed through each device was measured and plotted as functions of both the windspeed and the heat flux. The results show that when buoyancy effects were dominant, i.e. internalheat source under low wind speed, the column performed best, followed by the combined deviceand lastly the turbine. When wind effects were dominant, the combined device worked best,followed by the turbine which was close to the column. Performance of the column was seen tosuffer from the external wind while that of the turbine and the combined device benefited from it.Performance of the combined device was found to be better than that of the turbine due to stackeffects gained by an increased throat height compared to the turbine’s. This observation suggestsa simple modification to boost performance of current commercial low-throat turbine ventilators.