摘要:This study proposes an optimization design to improve the accuracy of fire risk models by combining the results of the UFSM (Urban Fire Spread Model, Japan) with the United States (US) Fire Simulation Software FDS6.7.3 (Fire Dynamics Simulator, FDS). Using parallel processing, the simulation time was dramatically reduced, and this may assist the risk factor analysis of buildings in a large area. Fire destroyed all seven main structures of the Shuri Castle World Heritage site on 31 October 2019, and this tool may have identified risk factors, which could have been mitigated and potentially prevented the building loss. Other historical buildings may benefit from using this tool to identify their relevant risk factors. This study completed a full-scale simulation of the 76 m × 45 m × 15 m area, which contained the nine temples, with 6.4 million grids for a simulation time of 600 s in 45 h. This tool can assist in input-data risk factor analysis and contribute to the improvement of protection technology for cultural heritage buildings.