COMPUTER-ANALYSIS OF THE EFFICACY OF EVAPORATIVE COOLING FOR GLASSHOUSES IN HIGH-ENERGY ENVIRONMENTS

Theoretical analysis of the efficacy of direct, single-stage evaporative cooling of glasshouses demonstrates how much temperatures in glasshouses can be reduced below those of the outside air. The analysis provides information on diurnal trends in glasshouse temperatures under specified radiant energy and outside temperature conditions. Increasing ventilation rates result in increased temperature reduction, but the increase is non-linear with air throughput rates. There is some input of water vapour due to humidification of the input air but transpiration from the crop contributes much more. The equations presented are relatively simple but can easily be expanded if necessary. They can be used for analysis of the effects of ventilation with uncooled air. © 1979.