Abstract
The airflow characteristics of eleven anti-insect screens used in the southwest islands were evaluated by means of a wind tunnel. The thread diameter of anti-insect screens ranged from 0.17 to 0.29 mm, and the porosity ranged from 0.25 to 0.68. Wind tunnel experiments indicated that the pressure loss through the screens was a function of porosity. Specifically, the pressure loss increased when the porosity decreased, even if the pores were approximately the same size. For instance, the pressure loss increased to 1.6 times when the porosity decreased by 18 %. It is recommended to examine the porosity, not the pore size, for the airflow characteristics of the anti-insect screens. The pressure loss through a screen was found to be a quadratic function of its porosity for a constant airflow velocity through the screen. Additionally, an examination of the adaptability of previously reported prediction equations for the pressure loss coefficient showed an error of 20 % or more for three screens.
