## THERMAL SCIENCE

International Scientific Journal

### A NEW HYBRID ALGORITHM FOR SOLVING TRANSIENT COMBINED CONDUCTION RADIATION HEAT TRANSFER PROBLEMS

**ABSTRACT**

A new algorithm based on the lattice Boltzmann method (LBM) and the Control Volume Finite Element Method (CVFEM) is proposed as an hybrid solver for two dimensional transient conduction and radiation heat transfer problems in an optically emitting, absorbing and scattering medium. The LBM was used to solve the energy equation and the CVFEM was used to compute the radiative information. The advantages of the proposed methodology is to avoid problems that confronted when previous techniques are used to predict radiative heat transfer, essentially, in complex geometries and when there is scattering and/or non-black boundaries surfaces. This method combination, which is applied for the first time to solve this unsteady combined mode of heat transfer, has been found to accurately predict the effects of various thermo-physical parameters such as the scattering albedo, the conduction-radiation parameter and the extinction coefficient on temperature distribution. The results of the LBM-CVFEM combination were found to be in excellent agreement with the LBM-CDM (Collapsed Dimension Method)this proposed numerical approach include, among others, simple implementation on a computer, accurate CPU time, and capability of stable simulation.

**KEYWORDS**

PAPER SUBMITTED: 2010-07-22

PAPER REVISED: 2010-12-30

PAPER ACCEPTED: 2011-02-24

**THERMAL SCIENCE** YEAR

**2011**, VOLUME

**15**, ISSUE

**Issue 3**, PAGES [649 - 662]

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