전산 해석에 의한 파풍망의 설치 효과와 최적 파이프 규격

Abstract

This study was carried out to(1) visualize the installation effect of an anti-wind net; (2) evaluate structural stability of typical anti-wind nets in Jeju; and (3) present the optimal specification of pipes in an anti-wind net for maximum instant wind velocities of 40 m/s and 45 m/s. The analyses were done for anti-wind nets with a mesh of 4 mm and a height of 3 m by using CFX and ANSYS. The results showed that the wind went down due to flow resistance when passing through an. anti-wind net. The anti-wind net with the supporting pipe being installed every two main columns was certainly unstable because the main column not sustained by the supporting pipe became cantilever. With regard to the position of a fixing point of the supporting pipe, von Mises stress on pipes was certainly increased as vertical positions of the supporting pipe were changed to be too lower or higher than an adequate position but there was little difference according to horizontal positions. The adequate vertical position was <TEX>$2{\sim}2.5\;m$</TEX> high from the ground. For a maximum instant wind velocity of 40 m/s, the optimal specification of pipes was a main column of <TEX>${\varphi}48.1{\times}2.1$</TEX> t@2,000, cross beams(bottom and top) of <TEX>${\varphi}26.7{\times}1.9\;t$</TEX>, cross beams(center) of <TEX>${\varphi}33.5{\times}2.1$</TEX> t/2ea and a supporting pipe of <TEX>${\varphi}31.8{\times}1.5$</TEX> t@2,000. In case of a maximum instant wind velocity of 45 m/s, the optimal specification of pipes with structural stability was a main column of <TEX>${\varphi}48.6{\times}3.25$</TEX> t@2,000, cross beams(bottom and top) of <TEX>${\varphi}26.7{\times}1.9\;t$</TEX>, cross beams(center) of <TEX>${\varphi}48.1{\times}2.1$</TEX> t/2ea and a supporting pipe of <TEX>${\varphi}31.8{\times}1.5$</TEX> t@2,000.