FDS Fire Modeling and Grid Sensitivity Analysis for Electrical Cable Fires in Open Conditions

In this study, numerical analysis of pyrolysis fire modeling using a FDS(fire dynamics simulator) was performed to evaluate the fire stability of electrical cable fires in nuclear power plants. For this purpose, a standardised fire modelling procedure applicable to electrical cable fires was developed, and fire modelling was performed for two and five cable tray conditions in an open space using FDS according to the proposed fire modeling procedure. A grid sensitivity analysis was performed to analyse the effect of grid size on the simulation results and to select the optimal grid size for use in pyrolysis fire modeling. The quantitative comparative analysis of fire simulation results was conducted by applying the analytical blind method to assess the thickness of the cable, heat release rate, and fire duration, along with the primary input parameters of the pyrolysis model, including the reference temperature for pyrolysis, heating rate, and pyrolysis range.