中文摘要：

本文采用了基于有限元的虚拟区域法在亚颗粒尺度上对单个焦炭颗粒在大空间的下落运动燃烧过程进行了数值模拟。控制方程为低马赫数可压缩流动方程及相应的能量和组分守恒方程。基于虚拟区域法的思想将颗粒视为浸入在背景网格中的有限大小区域,在有限元方法的离散方程中引入拉格朗日乘子保证颗粒区域速度场的刚体运动以及能量和组分方程边界条件。各方程采用分离变量求解的分步方法求解。本文给出了焦炭颗粒沉降燃烧的计算结果,同时证明了虚拟区域法可用于亚颗粒气固燃烧模拟。

英文摘要：

A numerical investigation of the combustion process of a char particle falling in an infinite large space is conducted.Fictitious domain finite element method is adopted to discretize the low maeh number governing equations of momentum,energy and species transportations.The particle is treated as a finite area immersed in a regular background mesh in the spirit of fictitious domain method,and Lagrange Multipliers are induced to enforce the rigid body movement and boundary conditions for Energy and Species equations.Segregated equations are solved and the results are illustrated.The competence of fictitious domain method for solving sub-particle scale gas-solid combustion problem is proved.