Gas Flow Analysis in Blast Furnace by Using Finite Element Method with Quadratic Elements

Abstract

A simulation of gas flow in a blast furnace was conducted by using the finite element method with quadratic elements. Vectorial form of the Ergun's equation was used for the equation of motion of gas in the packed bed. According to the variational principle, the discretization equation was derived from the equation of motion together with the equation of continuity. As for the infurnace structures required for numerical calculation, layered structure of are and coke, cohesive layer and raceway zone were taken into account. Simulation computations were carried out for some different configurations of cohesive zone and/or some different distributions of particle size. A numerical computation was performed to obtain the distributions of gas flow and pressure for the case in which the whole are layer consisted of double layers of different particle size.
The results indicated that the finite element method with quadratic elements gave much higher precision for gas flow computation than the finite element method with the simplex elements which was used previously. This simulation model makes it possible to estimate the changes in the distributions of gas flow and pressure which are caused by change in particle size distribution or bed structure. It enables also to evaluate the effect of the fine-particle-charge on the gas flow distribution.