Simulation Study on Combined Clapboard and Air Channel Ventilation for Extra-long Tunnels in Arctic-Alpine Regions
In order to study the effect of clapboard ventilation for extra-long tunnels in arctic-alpine regions,based on the Ganqing tunnel project,numerical simulation and theoretical calculation methods were adopted to study the influence of different air cabin parameters on the ventilation efficiency,with the length of the air cabin,fan position and the length of the middle baffle as variables.Under the condition of the optimal parameters of air cabin,further simulation calcula-tions were conducted to obtain the optimal position of air channel outlet.The results show that under the precondition of ensuring normal air supply to the heading face,under 30 m length of the air cabin,the location of the fan in the middle of the air cabin,and 6 m length of the middle baffle,the flow field distribution in the air cabin is stable,less affected by the vortex,with best ventilation effect.Comparing the velocity contour and wind speed variation curves at different dis-tances between the face and the air channel outlet,the jet cannot fully develop in the case of close distance between the air channel outlet and the face.In the case of far distance between the air channel outlet and the face,due to continuous dynamic energy transfer between the jet wind and the air in the tunnel,excessive dynamic energy of the jet wind is lost,resulting in the failure of the jet to reach the face.Therefore,the optimal distance for arranging the outlet location of the air channel is 25 m.It can provide reference for similar projects.
extra-long tunnelnumerical simulationair cabin parametersair channel outlet position
万方数据
维普
