Amirkabir University of Technology Amirkabir Journal of Mechanical Engineering 2008-6032 53 Issue 5 (Special Issue) 2021 07 23 Numerical investigation of compartment fire under maximum and minimum of natural ventilation using flamelet generated manifold combustion model Numerical investigation of compartment fire under maximum and minimum of natural ventilation using flamelet generated manifold combustion model 3335 3350 4100 10.22060/mej.2020.18086.6729 FA Mohamad Safarzadeh Tarbiat Modares University Ghassem Heidarinejad Tarbiat Modares University Hadi PasdarShahri Assistant Professor, Faculty of Mechanical Engineering, Tarbiat Modares University Journal Article 2020 03 10 When the fire in the room reaches a critical state, the fire can create hazards for the upper floors. In this paper, different fire cases with more and less natural ventilation than the critical state are discussed, and the temperature, velocity, and toxic species are discussed. A two-floor building is simulated using a large eddy simulation and PIMPLE algorithm and how the fire spreads upstairs is examined. Fuel flow rates are considered at three heat release rates of 500, 1000 and 5000 kW. The flamelet-generated-manifold combustion model is used to analyze toxic species and the results are compared with the experimental results. The relative error is less than 15%. With increasing fuel heat release rates, the upper floor is more exposed to fire hazards such that if the heat release rate is 500 kW, the temperature in the second floor reaches 390 K and the COspecies reaches 25 ppm. But if the heat release rate is below 1000 kW, the upper floor will not be at particular risk. Generally, the level of diffusion of CO₂ into the second floor is lower than the toxicity level for humans (25-50 ppm) and the second floor is not endangered for CO₂ gases. When the fire in the room reaches a critical state, the fire can create hazards for the upper floors. In this paper, different fire cases with more and less natural ventilation than the critical state are discussed, and the temperature, velocity, and toxic species are discussed. A two-floor building is simulated using a large eddy simulation and PIMPLE algorithm and how the fire spreads upstairs is examined. Fuel flow rates are considered at three heat release rates of 500, 1000 and 5000 kW. The flamelet-generated-manifold combustion model is used to analyze toxic species and the results are compared with the experimental results. The relative error is less than 15%. With increasing fuel heat release rates, the upper floor is more exposed to fire hazards such that if the heat release rate is 500 kW, the temperature in the second floor reaches 390 K and the COspecies reaches 25 ppm. But if the heat release rate is below 1000 kW, the upper floor will not be at particular risk. Generally, the level of diffusion of CO₂ into the second floor is lower than the toxicity level for humans (25-50 ppm) and the second floor is not endangered for CO₂ gases. https://mej.aut.ac.ir/article_4100_a3ec6dd8d538712a581e5b24726ce062.pdf