Numerical Simulation Study On Construction Ventilation In Long Single Tunnel

Study and analog simulation for long single tunnel ventilation play an important role in practical engineering, and it aim at sending fresh air in constantly and poison gas out, health protection of worker and working condition of themselves. Ultimately, it will ensure operator for construction to be safe and improve productivity efficiently. However, some contractors have not realized the importance of ventilation in construction; making the operators work under a bad environment of poison gas and bug dust. Just base on this, the thesis for study and research on tunnel ventilation have very important significance.The article gave more detailed discussion on theories of the water tunnel ventilation theory and computational fluid dynamics (CFD), and on that basis, it applies Computational Fluid Dynamics (CFD) to 6# tunnel's forced ventilation system in main canal for water diverting project, and simulate air flow velocity on the tunnel.This article also introduces that the establishment of model corresponding to 5×2000m practical ventilation construction, and it build use three different discrete ways:first by the first order discrete method, then the second-order, finally using velocity gradient grid cell to improve positioning and encryption, the second-order discrete method is adopted to energy equation, the results from three calculation methods and were compared.Through the actual measurement, harmful gas and dust concentration and the actual value of the wind was detected. The thesis demonstrates the correctness of this model simulation via experimental results and data comparison analysis.Based on the numerical simulation and measured data, analyze the actual project-based Section 440 meters with forced ventilation of the weak side, two solutions were used to process the actual project, the two methods were forced ventilation air duct different distances from the exit face ventilation works on the actual simulation, selected five different locations to simulate the analysis shows that the hair dryer from the best export from the face; and where appropriate add a jet fan on ventilation in practical engineering simulation, selected three different positions for simulation analysis shows that the jet fans to set the optimum position.The above two methods of numerical simulation, both the actual works to achieve the desired results, with practical engineering applications.