Simulating And Experimental Study On Temperature Field Of Fire In Bidirectional Ventilation Highway Tunnel

With the development of construction of our country highway tunnel, and lengthincreasing, the current many research on the temperature field of fire in road tunnel, relativelyspeaking, less on the fire temperature field combine with the escape and evacuationtechnology of the vehicles and person in fire double holes one-way bidirectional ventilationhighway tunnel.Based on the large slope of the Lotus Road Tunnel, study on the temperaturefield of the tunnel by numerical simulation and experimental research, to aim at studying ontunnel fire evacuation safety distance and safety evacuation routes in the double holesone-way four lane highway tunnel.According to the standard calculate air demand value of the lotus road tunnel doublelines, and the air exchange ventilation principle and using conditions, Assuming applicationof interchangeable ventilating in lotus tunnel, through calculating the range of Lotus Tunnelopening ventilation passage position，adopt to combine theoretical calculation and CFDnumerical simulation calculation method, hypothesis and simplified numerical simulationmodel of tunnel, to study on air exchange ventilation method applicability in Lotus tunnel anddetermine the best position for opening the cross passage. Numerical simulation andtheoretical analysis results for providing reference and guidance role in the application of airexchange ventilation mode in the lotus tunnel.Using the ANSYS/FLOTRAN element to establish the proportion of Lotus Road Tunnelnumerical model, through a lot of three-dimensional numerical simulations, analyzing of thetemperature field, velocity field, pressure field in steady state of different fire scale inhighway tunnel under different wind speed, drawing the tunnel fire temperature fielddiffusion regularity and fire pressure effect on the tunnel longitudinal ventilation airflow, todetermine the critical ventilation velocity in different scale fire. To define boundaryconditions for the next step of numerical simulation of the tunnel fire transient.By abundance of transient numerical simulation in the different fire scale at the criticalwind speed, getting the distribution of transient temperature field of different scale fire in roadtunnel. According to the relationship between staff tolerate temperature and the longest time,reference to the analysis results of transient numerical simulation, get staff retention time atdifferent locations away from the fire point downstream, determination of the escaping safetransverse passage position at critical wind velocity in fire downstream. Formulate windmachine accident ventilation direction and escaping rescue evacuation routes in case of fire atdifferent locations in the Lotus Road Tunnel.Acquisition and analysis of fire temperature model in tunnel. Verifying the result ofnumerical simulation by the temperature distribution of small and medium fire scale model tests in the laboratory, comparing and analyzing of difference results of the simulation and thetest, to further improve the accuracy of long highway tunnel fire critical wind speed and checkthe best location of the vehicle personnel safety evacuation transverse passageway in the firedownstream, to provide reference for the Lotus highway tunnel fire protection and rescue.