등가누출직경을 적용한 도시가스 감지기의 설치 위치에 대한 수치 해석적 연구

In this study, the location of gas detectors installed in urban gas-using facilities was investigated by using Computational Fluid Dynamics(CFD). Three-dimensional incompressible flow fields coupled with a κ-ε turbulence model were solved by using the equivalent leakage diameter to efficiently analyze the sonic jet leakage. Numerical simulation consisting of twenty methane gas leakage scenarios with various leakage hole sizes and gas pressures provided quantitative data of a detectable height that depends on an alarm set concentration. Lowering the alarm set concentration from 25% of Lower Explosive Level(LEL) to 20% of LEL was found to increase the detectable heights by 23∼31%. Although the maximum width of 20% contour of LEL was increased by 16%~30% compared to that of 25%, it was found that the width of the 25% contour of LEL predicted by CFD was as quite a small as about 30 ㎝.