Study on heat exhaust efficiency of side double point smoke exhaust mode
In this paper,we take a highway tunnel with a side double-point smoke exhaust mode as the research object and quantitatively analyze the heat exhaust effect from the perspective of the heat exhaust efficiency at the side smoke exhaust vent.Firstly,we use the dimensionless analysis to derive the dimensionless formula between the heat exhaust efficiency of the side smoke exhaust vent and the four influencing parameters of fire heat release rate,smoke exhaust air velocity,smoke exhaust vent height from the ground,and smoke exhaust vent spacing.Then we establish a numerical model by FDS and conduct a simulation analysis to determine the relationship between the heat exhaust efficiency and these four influencing parameters.The numerical model is established by FDS and simulated to determine the relationship between the heat release efficiency and these four influencing parameters.The results show that in the side double-point smoke exhaust mode,the heat exhaust efficiency decreases by-0.33 order of magnitude with the increase of fire heat release rate,increases by 0.23 order of magnitude with the smoke exhaust velocity,increases by 1.25 order of magnitude with the smoke exhaust height from the ground,and decreases by-0.57 order of magnitude with the smoke exhaust spacing.Finally,through linear fitting,the quantitative relationships between the four influencing parameters and the heat exhaust efficiency are obtained,and a prediction model of the heat exhaust efficiency at the smoke vent under the side double-point smoke exhaust mode considering the influence of suction penetration was established,with a correlation coefficient of 0.957,indicating that the prediction ability of the model is good and the reference value is credible and high.The results of the study can provide a reference for the design of the tunnel-side smoke exhaust system.
safety engineeringheat exhaust efficiencyside double point smoke exhaustdimensional analysisnumerical simulation