挡气板对综合管廊燃气泄漏扩散影响规律研究*

为研究挡气板对综合管廊燃气泄漏扩散影响规律，采用Fluent 软件模拟增设挡气板条件下泄漏燃气浓度分布特性，研究挡气板对探测效果及危险区域分布影响规律。结果表明:无通风情况下，增设挡气板可提升探测效果；正常通风条件下，探测效果无明显提升；挡气板高度达到0.5 m后，继续增加设置高度，探测效果无显著提升；无通风条件下，受挡气板区间段阻挡作用影响，燃气浓度危险区域扩张速度减小；正常通风条件下，挡气板背风侧安全区域间接促进泄漏燃气扩散排出，可有效防止管廊内部燃气聚集。研究结果可为优化综合管廊燃气舱可燃气体探测布置方案提供新思路与理论依据。

Study on influence laws of gas baffle on gas leakage and diffusion in utility tunnel

In order to study the influence laws of gas baffle on the gas leakage and diffusion in the utility tunnel,the Fluent software was used to simulate the concentration distribution characteristics of the leaked gas with adding the gas baffle,and the influence laws of gas baffle on the detection effect and the distribution of dangerous area were studied.The results showed that adding the gas baffle could improve the detection effect in case of without ventilation,and the improvement of detection effect was not significant in case of normal ventilation.When the height of gas baffle reached 0.5 m,the improvement of detection effect was not significant when increasing the setting height continuously.Under the condition of without ventilation,the expansion speed of the dangerous area of gas concentration decreased due to the restriction of the internal section of gas baffle.Under the normal ventilation,the safety area formed on the leeward side of gas baffle indirectly promoted the diffusion and discharge of the leaked gas,and effectively prevented the accumulation of gas in the utility tunnel.The results provide a new idea and theoretical basis for optimizing the layout scheme of the combustible gas detection system in the gas cabin of the utility tunnel.