火灾模拟结果误差分析的函数分析法

Error Analysis of Fire Simulation Results Based on Method of Function Analysis

火灾试验结果和模拟预测结果常能表达成关于时间变化的曲线,为定量描述两种随时间变化曲线间相符合的程度,引入误差分析的函数分析法。采用适合于低Mach数流修正的N-S方程描述烟气的输运过程,使用大涡模拟和Smagorinsky亚格子模型,对封闭空间内的火灾过程进行数值模拟;对其计算结果的分析表明,函数分析法能定量对模拟预测曲线与试验曲线间的差别进行描述,模是两曲线值大小的相对误差的度量,余弦是两曲线形状相似程度的度量。

Abstract： Experimental results on fire and predictive results by simulation can commonly be expressed with a curve related to time. To quantitatively determine the consistency of the two curves, method of functional analysis is introduced to analyze the errors between them. The process of fire in a close space is numerically simulated by large eddy simulation with Smagorinsky subgrid-scale model; this simulation adopts Navier- Stokes equations to describe the transport of smoke and heat, which is suitable for compressible flow with low Mach number. The calculation result shows that the method of functional analysis can be used to describe the errors between the two curves, norm is a measure of the relative errors between them, and cosine is a quantitative measure of similarity in curve shape.