Abstract
Ventilation opening covered with screen are being utilized for eliminating insect infestationsin the greenhouses in Taiwan. In this study, airpermeability of seven types of insect screens wasinvestigated. The result showed that air exchangeindex (n) was in the region of 1.70-1.88, and theair exchange rate (a. m3/(m2·min·Pa1/n)) increased with larger porosities of screen by a function of a=1.36×102.35μ. When Reynolds number were about 400, pressure loss coefficient (ζ) obtained for each screen became constant, and the relation between ζ and μ was deduced to ζ=0.95(1-μ)/μ2.
