摘要
为探明瓦斯隧道施工过程中瓦斯积聚现象的发生原理和开挖面流场、瓦斯涌出及扩散规律,建立压入式通风三维数值计算模型,研究瓦斯涌出量、风量大小和风管位置等因素对瓦斯扩散的影响。结果表明:在瓦斯涌出面附近区域,瓦斯浓度大梯度变化现象主要发生在回流区,且伴随瓦斯积聚现象发生,但随着与瓦斯涌出面距离的增加,瓦斯浓度逐渐趋于均匀;瓦斯涌出量越大,对流场影响越严重且漩涡范围越大,漩涡对瓦斯扩散有滞留作用;增大通风量可以有效控制瓦斯积聚,但风管布置位置只在一定范围内对瓦斯积聚影响较大。
In order to ascertain the generating principle of gas accumulation and the rules of ventilation flow field of tunnel face, gas emission and diffusion during the process of tunnel construction, the 3 D numerical calculation models of forced ventilation are established to study the impact of gas emission quantity, air quantity and air duct positions on gas diffusion. The result shows that （ 1 ） the large gradient change of gas concentration is in backflow zone and the phenomenon of gas accumulation appears near the gas emission face, however, the gas concentration tends to be uniform with the distance from gas emission face increasing; （2） the lager the gas emission, the greater the effect on the flow field and the broader the scope of whirlpool, and the whirlpool has a retention effect on the gas emission; （3） Increasing the ventilation quantity can effectively control gas accumulation, but the arrangement of air duct positions exerts larger impact on the gas accumulation only within a certain range of positions.
出处
《公路交通科技》
CAS
CSCD
北大核心
2015年第2期119-126,共8页
Journal of Highway and Transportation Research and Development
关键词
隧道工程:施工通风
数值模拟
瓦斯涌出
瓦斯积聚
扩散
tunnel engineering
construction ventilation
numerical simulation
gas emission
gas accumulation
diffusion
