寒区隧道空气幕保温技术效果分析

Analysis on Effect of Air Curtain Insulation Technology for Tunnels in Cold Regions

为研究寒区隧道空气幕保温技术的保温效果,以某隧道为设计背景,应用相似理论和量纲分析法,首次搭建由外界环境控制装置、棚洞模型、空气幕射流控制装置和温度测试装置4部分组成的模型试验系统。试验采用控制变量法分析不同工况下空气幕保温技术的效果,研究结果表明:空气幕保温技术的最优射流角度为30°~40°;当外界温度为-10℃,外界风速为2 m/s时,一道空气幕墙可以满足隧道的防寒保温需求;空气幕射流速度应根据隧址处的自然环境变化,才能有较好的防寒效果;寒区隧道空气幕保温技术的保温原则为以加热为主、隔风为辅;当串联多道空气幕共同工作时,最佳串联间距为30 m。模型试验填补了寒区隧道空气幕保温技术试验的空白,结果可为我国寒区隧道工程建设提供思路和参考。

In order to study the thermal insulation effect of air curtain thermal insulation technology for tunnels in cold regions,based on the design background of a tunnel,this paper applied the similarity theory and dimensional analysis method to build a model test system composed of four parts:external environment control device,shed tunnel model,air curtain jet control device and temperature testing device for the first time.The experiment analyzed the effect of air curtain insulation technology under different working conditions using the control variable method.and achieved the following research results:the optimal jet angle of air curtain insulation technology was 30°~40°.At the external temperature of-10℃and the external wind speed of 2 m/s,an air curtain wall can meet the cold insulation requirements of the tunnel.The jet velocity of air curtain should be changed according to the natural environment at the tunnel site,so as to have a better cold protection effect.The thermal insulation principle of the air curtain thermal insulation technology for tunnels in cold regions should be with heating as the primary method and air isolation as the secondary.When multiple air curtains are connected in series to work together,the optimal distance between them was 30 m.This model test fills the blank of tunnel air curtain insulation technology test in cold regions,and the results can provide ideas and references for tunnel construction in cold regions in China.