| In order to meet the need of the rapid and sustained growth of economy,transportation is regarded as one strategic objective of national economic development.Highway tunnel construction is into a rapid period of development: the constructiontechnique and economic efficiency are greatly improved, while the number and length ofthe highway tunnel also reaches new heights. Thought developed fast, it brings the problemof environmental pollution in the tunnel. The high temperature and harmful gasses in thetunnel affect the physical and mental health of construction workers and passengersseriously, in the case of tunnel fire, they even threaten personal safety. In addition,environment in highway tunnel has become a hot research topic in the research of highwaytunnel.Environmental pollution in the highway tunnel is divided into three parts: thepollution in the process of paving asphalt pavement, automobile exhaust in the process oftunnel operation, smoke airflow with high temperature in tunnel. Based on these patternsof pollutions, the paper discussed the distribution laws of air pollution and temperature intunnel and proposed the factors affecting the distribution, by means of a ComputationalFluid Dynamics software ANSYS-FLUENT, different models of tunnel.The results show: the forced ventilation was an affective method to solve the problemof high temperature in tunnel execution area. The distribution law of harmful gasses in thetunnel was that the concentration of gasses in the middle area was higher than that on bothsides; the concentration of the gasses in the bottom area was higher than that in the top area.The ventilation velocity and the vehicle speed were the major factors effecting thedistribution of harmful gasses in tunnel. In the case of fire, Smoke ventilation and coolingefficiency of three draft types in the tunnel can be ordered that all horizontal ventilation isbest, semi-transverse ventilation is better and longitudinal ventilation is worst. |
PDF Full Text Request