CFD simulations
Due to the fast development in computer technology, Computational Fluid Dynamics (CFD) has become an accepted tool in fire safety engineering (RiMEA-guideline, GFPA-guideline).
Since the physical phenomena of fluid dynamics and fire are very complex, some of these effects are modelled. The effect of turbulence, pyrolysis or thermal conduction are still modelled but not calculated in a small scale. Due to that, results are obtained fast. Against that, a huge amount of validation work is needed to provide capable results. For this validation, results of real fire tests are required. IFAB has a massive fire test data base available from full scale tests, so it is able to verify the CFD models against experimental data in most cases. With its huge experience in fire testing, IFAB can generate needed validation data by itself if data is not available. This sets IFAB apart from organizations that use CFD without validation.
Examples for CFD simulations are:
– Smoke and toxic gas distribution
• Proof of function for smoke and heat venting systems
• Analysis and optimization of smoke and heat venting systems
• Calculation of available safe egress time (ASET)
• Calculation of detection times of smoke detectors
– Simulation of thermal distribution
• Proof of part capability
• Determination of thermal input to objects and humans
• Calculation of detection times of heat detectors
– Effect of fire-fighting system
• Proof of efficiency
• Optimization of setting
– Simulation of evacuation
• Calculation of required safe egress time (RSET)
• Analysis and optimization of escape paths
• Proof of escape path efficiency
• Influence of heat, smoke and toxic gases on evacuees
– Simulation of design fire curves
• Determining the heat release rate (HRR) of rail vehicles