# Theoretical and Numerical Simulation Research on Fire of Large-Span Spatial Structures
The prediction methodologies and models for fire temperature fields have seen extensive development, with each approach predicated on the foundational assumption of a regional model--that the smoke layer's temperature and component concentration are uniformly distributed, thereby yielding the average temperature of the flue gas layer. In the realm of fire zone model studies, [PERSON] [16] employed this model to calculate a 2 MW fire source, discussing the temperature field distribution and validating the model's accuracy in qualitatively describing fire scenarios. Building upon experimental research, [PERSON] et al. [17] introduced a smoke plume model adept at characterizing the progression of indoor fire smoke layers, laying the groundwork for subsequent finite element analyses. Advancing computer technology has rendered the numerical simulation of large space fires increasingly sophisticated, with scholars proposing diverse models including empirical, regional, and field models. Notably, the field model, while the most complex and computationally demanding, offers simulations closest to real fire temperature fields. Current computational tools leveraging the field model include FDS, FLUENT, and PHOENICS [18; 19; 20; 21]. [PERSON] [22] resolved the unsteady N-S equations, thereby enhancing the applicability of field simulation methods to large space temperature field simulations, leading to the development of the FDS fire simulation software. [PERSON] [23] compared experimental and numerical simulation results from two-scale model fire tests, demonstrating the efficacy of FDS in simulating fire scenarios. Numerous scholars have since utilized field simulation to model fire temperature fields [24; 25; 26; 27]. For instance, [PERSON] et al. [28] utilized PYROSIM to simulate a fire scenario at the Yangtze River International Conference Center, extracting essential fire parameters and determining optimal evacuation times. [PERSON] et al. [29] conducted numerical simulations of fires in air-supported coal sheds, focusing on smoke layer temperature and concentration. [PERSON] et al. [30] applied the ISO834 standard heating curve and empirical formulas for large space building fires to calculate the time-temperature field model at each node of a cable dome. [PERSON] et al. [31] examined the fire temperature field distribution characteristics of inflatable membrane structures using FDS, with a focus on the membrane surface temperature field distribution from a single fire source at varying positions. [PERSON] et al. [32] confirmed the feasibility of simulating temperature field distribution using thermal-fluid-solid coupling dynamic boundary conditions, refining traditional temperature field analysis methods, and establishing a fire temperature field model for rectangular air-supported membrane structures. [PERSON] et al. [33; 34] introduced a machine learning (ML) framework that integrates computational fluid dynamics (CFD) and finite element method (FEM) to predict structural fire responses based on numerical data. [PERSON] et al. [35] found that the hot smoke near the smoke outlet of the spatial structure under fire was affected by the convection of outdoor cold air, and the temperature of the membrane surface was 5 \({}^{\circ}\)C\(\sim\)10 \({}^{\circ}\)C lower than that of the other positions. [PERSON] et al. [36] conducted a fire test on a full-size gas-branched membrane structure in a large space, and found that the maximum temperature near the membrane can reach 250 \({}^{\circ}\)C, which is below the burnout temperature of the membrane. [PERSON] et al. [37] created a finite element analysis (FEA) model for the RC structures and solved using Abaqus software. The structure was heated according to the real and standardized fire curves. The real fire temperatures were up to 70% lower than those predicted by the standard. Despite the field model's robust theoretical foundation, its complexity and the extensive knowledge required for its application make it challenging for engineering and technical staff to embrace.