Model Experimental Study on the Heat Exhaust Efficiency in the Central Smoke Exhaust Mode with Independent Smoke Duct in Extra-long Highway Tunnel

How to control the fire smoke of the extra-long highway tunnel is one of the important and difficult problems in fire protection study. It is impossible to get an integrated evaluation of the smoke control effect through some static indexes such as the smoke temperature, concentration, pressure or smoke control area, and there is also a high possibility of chanciness and error. Through the reduced-scale experiment, we get the rule that there is a linear increasing trend for the smoke temperature against time in different situations, in order to suggest the heat exhaust efficiency lambda be the key parameter to evaluate the smoke control effect in central exhaust system. The results show that lambda can make up the disadvantages of the above static indexes and is reliable and practical.