地铁列车火灾烟气流动及传热的数值模拟

CFD simulation of smoke flow and heat transfer under subway station fire

以多相流燃烧与烟气传递过程的基本假设和数学模型为基础,运用CFD软件ANSYSCFX10.0对某地铁站列车火灾的烟气流动与传热过程进行了数值模拟研究。气体的湍流流动采用浮力修正的双方程k-ε湍流模型描述,以高温热源、烟气组分源模拟火源,辐射由Rosseland模型考虑,模拟了三维非稳态火灾烟气流动与传导、对流和辐射的复合传热过程,分析了火灾条件下流动、热以及烟气的传递规律,并对燃烧条件下由于密度变化引起的扼流效应、浮力效应进行了分析。

Based on the basic assumption and models of multiphase combustion and smoke transport,numerical simulation of smoke flow and heat transfer process on a subway train fire is carried out by CFD software-ANSYS CFX 10.0.A three dimensional dynamic field simulation of multitude heat transfer process including smoke flow,and the heat transfer of conduction,convection and radiation is accomplished,in which two equations k-ε turbulent model with buoyancy modification is used and Rosseland radiation model is applied to take radiation into consideration.The fire is set as a heat source with smoke components.The transport process of fluid flow,heat and smoke transfer is discussed.The throttle effect,floatation effect resulted from the change of air density are discussed in detail.This work will provide the theoretic base for the study of subway fire simulation.