Development of the Rooftop Ventilator Powered by Photovoltaic Energy

10.6451/JETE.201109.0370

Feng-Chyi Duh；Tsung-Han Li

Rooftop ventilator ； Natural convection ； Forced convection ； Evaporative cooling

工程科技與教育學刊

8卷3期（2011 / 09 / 01）

370 - 380

英文

This study develops a newly rooftop ventilator powered by photovoltaic energy. An experiment is performed to investigate the simulated model's ventilation performance. Photovoltaic energy were employed to active the rooftop ventilator, three main heat transfer mechanisms enable the indoor temperature to be decreased through the new rooftop ventilator: method 1 is to use the device design produce natural convection, method 2 is to drive fan produce forced thermal convection, and method 3 is to use atomized sprayer absorb heat of vaporization. According to preliminary experimental data results, the maximum effect of decreasing the temperature by natural convection alone was 18.2℃ (23.9% temperature drop); when combined with forced convection, the maximum effect was decreased by 24.6℃ (44.2% temperature drop). When the forced convection was combined with the endothermic process of evaporative cooling, the maximum effect of decreasing temperature was 15.7℃ (31.4% temperature drop). When the device was powered by a self-powered photovoltaic system, experiments showed it greatly improved the indoor air quality.