Advances in the discrete ordinates and finite volume methods for the solution of radiative heat transfer problems in participating media

2014 ◽  
Vol 145 ◽  
pp. 121-146 ◽  
Author(s):  
Pedro J. Coelho
Keyword(s):  
Heat Transfer ◽  
Finite Volume ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Finite Volume Methods ◽  
Discrete Ordinates ◽  
Participating Media ◽  
Transfer Problems

Numerical Solution of Radiative Transfer in a Real-Participating Media

2016 ◽  
Vol 138 (9) ◽  
Author(s):  
Hanene Belhaj Ali ◽  
Hajer Grissa ◽  
Faouzi Askri ◽  
Sassi Ben Nasrallah
Keyword(s):  
Heat Transfer ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Control Volume ◽  
Computational Time ◽  
Discrete Ordinates ◽  
Model Parameters ◽  
Band Model ◽  
Zonal Method ◽  
Participating Media

In this paper, the control volume finite element method (CVFEM) is coupled with the weighted sum of gray gases model (WSGGM) to study the radiative heat transfer in a nongray medium. To the best of our knowledge, the CVFEM–WSGGM is applied for the first time to simulate real-gas. The accuracy of the proposed method is tested through one- and two-dimensional radiative heat transfer within an enclosure filled with a single composition (water vapor or carbon dioxide) or a mixture of H2O, CO2, and N2. Compared to the discrete ordinates method (DOM)–statistical narrow band model (SNBM), the proposed method, using the WSGG model parameters due to Smith or Farag, yields much accurate results than the zonal method (ZM)–WSGGM and DOM–WSGGM. In addition, the present method needs very less control volumes and angles, and consequently computational time, compared to the DOM and ZM coupled with WSGGM.

Application of Modified Discrete Ordinates Method With the Concept of Blocked-Off Region Method to Radiative Heat Transfer Problems in Irregular Geometries

2010 ◽  
Author(s):  
H. Amiri ◽  
S. H. Mansouri ◽  
A. Safavinejad
Keyword(s):  
Heat Transfer ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Curvilinear Coordinates ◽  
Discrete Ordinates ◽  
Test Problems ◽  
Discrete Ordinates Method ◽  
Irregular Geometries ◽  
Transfer Problems ◽  
Ray Effects

The discrete ordinates method (DOM) for the solution of radiative heat transfer problems have received significant attention and development owing to their good compromise between accuracy, flexibility and moderate computational requirement. However, the DOM suffers from the ray effects related to the discretization of the angular distribution of the radiation intensity. The modified discrete ordinate method (MDOM) proved to significantly mitigate ray effects originated from discontinuities or abrupt changes of the wall temperature. This article presents blocked-off region treatment of irregular geometries using a modified discrete ordinates method in Cartesian coordinates. The Cartesian based 2D algorithm can be used to solve radiative heat transfer in irregular geometries by dividing the region into active and inactive regions. It is easier and convenient way of handling 2D irregular geometries than to write an algorithm in curvilinear coordinates. It is capable of handling participating (absorbing, emitting and isotropic or anisotropic scattering) or non participating gray media enclosed by gray diffuse walls. Both radiative and non-radiative equilibrium situations are considered. The walls of the enclosures can have either heat flux or temperature boundary conditions. Cases with curved and obstacle and radiation shield are considered. Some test problems are considered and results are validated with the available results in the literature. Results are found to be accurate for all kinds of situations.

scholarly journals Assessment of radiative heat transfer impact on a temperature distribution inside a real industrial swirled furnace

2020 ◽  
Vol 24 (6 Part A) ◽  
pp. 3663-3672
Author(s):  
Filip Juric ◽  
Milan Vujanovic ◽  
Marija Zivic ◽  
Mario Holik ◽  
Xuebin Wang ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Temperature Distribution ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Combustion Process ◽  
Combustion Model ◽  
Discrete Ordinates ◽  
Participating Media ◽  
Combustion Systems

Combustion systems will continue to share a portion in energy sectors along the cur-rent energy transition, and therefore the attention is still given to the further improvements of their energy efficiency. Modern research and development processes of combustion systems are improbable without the usage of predictive numerical tools such as CFD. The radiative heat transfer in participating media is modelled in this work with discrete transfer radiative method (DTRM) and discrete ordinates method (DOM) by finite volume discretisation, in order to predict heat transfer inside combustion chamber accurately. The DTRM trace the rays in different directions from each face of the generated mesh. At the same time, DOM is described with the angle discretisation, where for each spatial angle the radiative transport equation needs to be solved. In combination with the steady combustion model in AVL FIRE? CFD code, both models are applied for computation of temperature distribution in a real oil-fired industrial furnace for which the experimental results are available. For calculation of the absorption coefficient in both models weighted sum of grey gasses model is used. The focus of this work is to estimate radiative heat transfer with DTRM and DOM models and to validate obtained results against experimental data and calculations without radiative heat transfer, where approximately 25% higher temperatures are achieved. The validation results showed good agreement with the experimental data with a better prediction of the DOM model in the temperature trend near the furnace outlet. Both radiation modelling approaches show capability for the computation of radiative heat transfer in participating media on a complex validation case of the combustion process in oil-fired furnace.

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