Dear all,

I started to work in the field of radiation modeling (fired furnaces) with CFD codes. To verify the radiation models I'm searching a 3D-example (simple geometry) to benchmark the models. A paper of Timothy W. Tong, published in HTD-Vol. 203, Developments in radiative heat transfer, ASME 1992 ("Summary on comparison of radiative heat transfer solutions for a specified problem")seems to be one good starting point for me. Within this paper there is discussed the radiative heat flux for fixed fluid properties in a rectangular enclosure for different radiation models.

For someone, who is more involved and expearienced in these topics, I have a question: Does this example still serves as a "state of the art" example of judging different radiation models (or exists - years passed by, new methods were modeled... - another well discussed benchmark model, ideally with a comparison also with experimental results?

Maybe someone can recommend me a paper reference or some adresses (including www) where I can find additional informations?

With best regards

Klaus-Peter

Hi Peter, You can verify your code on 3-D rectangular problem (Selçuk, N. and Kayakol, N., Evaluation of Discrete Ordinates Method for Radiative Transfer in Rectangular Furnaces, Int. J. Heat Mass Transfer, 40, 213-222, 1997) or cylindrical problem (Selçuk N. and Kayakol N., Assessment of Discrete Ordinates Method for Radiative Transfer in Cylindrical Furnaces, Second symposium (Int.) on Radiative Heat Transfer, ICHMT, Kusadasi, Türkiye, June, 1997) of Selçuk. The exact solutions are produced by Selçuk. The problem is based on data taken from a large-scale perimental furnace with steep temperature gradients typical of operating furnaces.

In these papers you can find answers to your questions about importance of judging different radiation models and validation procedures.

Validation studies with experimental data or exact solutions is still main concern.

If I can be of further assistance, please let me know.

Nuray Kayakol

Hi, I have a few additional questions regarding thermal radiaton. I am interested in surface-to-surface thermal radiation without interaction with a gas. My application are surface temperature on components in the engine bay. Do you, or anyone else, know any good 3d validation examples?

Regards

Anders

I don't know such a 3D validation example. But absorption coefficient ka(1/m) represents thermal radiation due to gas medium. As ka goes to zero surface-to-surface thermal radiation becomes more dominant than gas radiation. What I mean is this: a 3D code can be applied to both a participating medium (CO2+H2O) and non-participating medium (air) by using appropriate ka values.