高架桥下天然气泄漏扩散研究

Gas Leakage Diffusion Research under the Viaduct

为了研究高架桥下架设天然气管道的可行性,并提出相应的指导施工意见一以济南市北园高架为例,建立高架桥下燃气泄漏模型,应用FLUENT软件分别模拟了无风条件下和有风条件下天然气管线泄漏的情况,结果表明无风条件下天然气会从泄漏侧向高架桥另一侧扩散,且高架桥下充满泄漏的天然气比较危险,在高架桥的两侧形成爆炸危险区域;在有风条件下,由于风速的搬运作用,天然气会沿风向向下风口处扩散,高架桥下面只有少量的天然气,并在泄漏口侧离地面3m以上的位置才形成爆炸危险区域,因此对地面车辆影响较小并提出高架桥下架设的燃气管线设置的意见:(1)应设置在城市风向的下风侧;(2)尽量减少燃气管道的接口;(3)架空管道沿线应设置燃气报警器.

Explore under the viaduct erect the possibility of gas pipeline, gas pipeline provides basis and guidance for under the viaduct. Take the north park viaduct for example, using Gambit to establish 44m by 18m two-dimensional gas pipeline leakage model under the viaduct. Using the FLUENT software to simulate software respectively under the condition of no wind and the wind under the condition of natural gas pipeline leakage. The results show that under the condition of no wind and gas will leak from the other side of the lateral viaduct diffusion, and under the viaduct is full of leakage gas more dangerous, formed in the both sides of the viaduct explosion danger area;In the case of wind, natural gas will spread along the wind direction and downward through the airway due to the transport of wind speed. Only a small amount ofnatural gas under the viaduct will form the explosion danger area when the leakage mouth is 3m above the ground. Therefore, it has little impact on ground vehicles. The opinion on the gas pipeline setting under the viaduct is put forward :(1) it should be set on the downwind side of the city wind direction;(2) The interface of gas pipeline should be minimized;(3) The gas alarm should be set along the aerial pipeline.