A Simulation And Study Of Direction Jet Ventilation In Qinling Zhongnanshan Road Tunnel

As the length of tunnel is no longer the mostly limiting factor because of the modern new ventilation development technology, longitudinal ventilation is more and more frequently used in large-long road tunnel ventilation. The expense on large-long road tunnel ventilation takes up about50%in the whole management cost, which results in the tunnel major concerned personnel all around the world focus on the research on the airflow velocity, pressure distribution, contamination concentration, ventilation and fire-guard in large-long tunnel. It makes sense that using ventilation system in large-long tunnel properly and economically, controlling the contamination, ensuring the normal ventilation. The research of the tunnel ventilation in our country was late, and the level is far behind other countries, which has become a constraining bottleneck in the development of tunnel construction.In this paper, choose the Qinling Zhongnanshan road tunnel for the study, according to the characteristics and requirements of longitudinal jet ventilation in the tunnel, based on the theoretical analysis,The paper take Qinling Zhongnanshan road tunnel as object of study, according to the characteristic and request of tunnel longitudinal jet ventilation, on the basis of theoretical analysis, conducts the numerical simulation research to flow quality of air in the tunnel with the application of Computational Fluid Dynamic (CFD)software.The main research content includes the following aspects:1. The research of reasonable installing height of the jet fan2. The research of reasonable installing spacing of the jet fan3. The research of effects of the outlet velocity of jet fan and the tunnel entrance wind velocity on the airflow in the tunnel4. The research of reasonable jet fan combination program in the large section with three roads 5. The research of reasonable installing location of the jet fan when the tunnel section changes suddenlyThe research mentality of the Paper:First of all, according to the characteristic of air flow field in the sector tunnel, build the mathematics、physics model suits in solution to aerodynamics characteristics and corresponding numerical calculus method; Apply the mathematics model and numerical calculus method through confirmation in actual project to the Qinling Zhongnanshan tunnel longitudinal jet ventilation system, calculate jet fans performance under different working conditions in the tunnel, and analyze the pressure field and velocity field in the tunnel. Based on this, select the most reasonable fans installation parameter, make the airflow regulation of jet fans on the air in the tunnel more reasonable. Thus, make the ventilation design scheme serve the purpose of energy-saving and reasonable.The study of this paper can be valued for the program and installation parameters on the longitudinal jet ventilation in the Qinling Zhongnanshan tunnel, and provide the theory basis for later long highway tunnel longitudinal ventilation system design.