Improvement of computational time in radiative heat transfer of three-dimensional participating media using the radiation element method

2002 ◽  
Vol 73 (2-5) ◽  
pp. 239-248 ◽  
Author(s):  
Shigenao Maruyama ◽  
Yuhei Takeuchi ◽  
Seigo Sakai ◽  
Zhixiong Guo
Keyword(s):  
Heat Transfer ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Three Dimensional ◽  
Computational Time ◽  
Participating Media ◽  
Element Method

Accelerate Iteration of Least-Squares Finite Element Method for Radiative Heat Transfer in Participating Media With Diffusely Reflecting Walls

2012 ◽  
Vol 134 (4) ◽  
Author(s):  
Wei An ◽  
Tong Zhu ◽  
NaiPing Gao
Keyword(s):  
Heat Transfer ◽  
Finite Element Method ◽  
Boundary Condition ◽  
Finite Element ◽  
Radiative Transfer ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Present Model ◽  
Participating Media ◽  
Element Method

A high reflectivity of walls often leads to prohibitive computation time in the numerical simulation of radiative heat transfer. Such problem becomes very serious in many practical applications, for example, metal processing in high-temperature environment. The present work proposes a modified diffusion synthetic acceleration model to improve the convergence of radiative transfer calculation in participating media with diffusely reflecting boundary. This model adopts the P1 diffusion approximation to rectify the scattering source term of radiative transfer equation and the reflection term of the boundary condition. The corrected formulation for boundary condition is deduced and the algorithm is realized by finite element method. The accuracy of present model is verified by comparing the results with those of Monte Carlo method and finite element method without any accelerative technique. The effects of emissivity of walls and optical thickness on the convergence are investigated. The results indicate that the accuracy of present model is reliable and its accelerative effect is more obvious for the optically thick and scattering dominated media with intensive diffusely reflecting walls.

Prediction of Radiative Heat Transfer in Industrial Equipment Using the Radiation Element Method

2001 ◽  
Vol 123 (4) ◽  
pp. 530-536 ◽  
Author(s):  
Zhixiong Guo ◽  
Shigenao Maruyama
Keyword(s):  
Heat Transfer ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Narrow Band ◽  
Particle Density ◽  
Three Dimensional ◽  
Wide Band ◽  
Band Model ◽  
Participating Media ◽  
Carbon Particles

The radiation element method by ray emission method, REM2, has been formulated to predict radiative heat transfer in three-dimensional arbitrary participating media with nongray and anisotropically scattering properties surrounded by opaque surfaces. To validate the method, benchmark comparisons were conducted against the existing several radiation methods in a rectangular three-dimensional media composed of a gas mixture of carbon dioxide and nitrogen and suspended carbon particles. Good agreements between the present method and the Monte Carlo method were found with several particle density variations, in which participating media of optical thin, medium, and thick were included. As a numerical example, the present method is applied to predict radiative heat transfer in a boiler model with nonisothermal combustion gas and carbon particles and diffuse surface wall. Elsasser narrow-band model as well as exponential wide-band model is adopted to consider the spectral character of CO2 and H2O gases. The distributions of heat flux and heat flux divergence in the boiler furnace are obtained. The difference of results between narrow-band and wide-band models is discussed. The effects of gas model, particle density, and anisotropic scattering are scrutinized.

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.

Coupling a Discrete Transfer Method to a View Factors Technique for Radiative Heat Transfer Modeling in Industrial Furnaces

2005 ◽  
Author(s):  
Youssef Joumani ◽  
Guillaume Mougin ◽  
Fouad Ammouri ◽  
Marc Till
Keyword(s):  
Heat Transfer ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Three Dimensional ◽  
Analytical Formula ◽  
Two Dimensions ◽  
Radiation Model ◽  
Participating Media ◽  
View Factors ◽  
Transfer Method

Air Liquide has been involved in the design of industrial furnaces (glass melting, reheating, aluminum, …) for several years. Thanks to that experience, known-how and expertise in modeling such applications have been developed. Dedicated simulation tools — 0D for global heat and mass balance, 1D for the prediction of longitudinal temperature profiles and 3D for detailed analysis — have been built. Each of them is very helpful when used relevantly and offers numerous opportunities at each step of the design of a furnace. In such kind of applications, the temperature levels are very high (up to 2500 K). As a consequence it is very crucial to simulate the radiative heat transfer as accurately as possible. This requires the use of a radiation model that can take into account complex geometries, non-isothermal media and various gas mixture compositions. Very often, three-dimensional simulations are necessary and reduction to smaller dimension problems is difficult or inadequate. The present paper introduces a new radiation model for computing two-dimensionally radiative heat transfer in an industrial furnace with a piecewise distributed load. To reduce the three-dimensional problem to two dimensions, the method consists in coupling the 2D radiation transport equation to a boundary condition based on view factors through an imaginary plane to homogenize the radiative behavior of the load surface. A solution procedure using the discrete transfer method associated to a weighted-sum-of-gray-gases database to deal with absorption and emission of a CO2-H2O mixture is proposed. Simulation results are finally compared to an analytical formula and then to a full-3D approach taking into account participating media, non-isothermal and gray walls. All tests show that this model can be used to simulate industrial configurations with a good accuracy.

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