Assessment of SLW-1 model in the presence of gray and non-gray particles

Date

2019-02-01

Author

Özen, Guzide
ATEŞ, CİHAN
Selçuk, Nevin
Külah, Görkem

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In this study, predictive accuracy of Gray Gas and SLW-1 approximations is benchmarked against Spectral Line-Based Weighted Sum of Grey Gases Model (SLW) in multidimensional enclosures involving gray/non-gray absorbing, emitting and scattering particles. Input data required for the radiation code and its validation are provided from two combustion tests previously carried out in a 300 kWt Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) test rig burning low calorific value Turkish lignite with high volatile matter/fixed carbon (VM/FC) ratio in its own ash. Comparisons reveal that SLW-1 approximation leads to one order of magnitude higher accuracy in heat flux and source term predictions compared to that of Gray Gas approximation in the presence of gray particles while maintaining a similar computational efficiency. In the presence of non-gray particles, SLW-1 approximation is again found to improve the predictive accuracy compared to that of Gray Gas approximation. However, it is seen that errors in heat flux and source term predictions with SLW-1 approximation are noticeably higher in the presence of non-gray particles compared to those with gray particles.

Subject Keywords

Radiative heat transfer, Non-gray particle radiation, SLW-1, SLW, Gas radiation

URI

https://hdl.handle.net/11511/30757

Journal

INTERNATIONAL JOURNAL OF THERMAL SCIENCES

DOI

https://doi.org/10.1016/j.ijthermalsci.2018.10.038

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

G. Özen, C. ATEŞ, N. Selçuk, and G. Külah, “Assessment of SLW-1 model in the presence of gray and non-gray particles,” INTERNATIONAL JOURNAL OF THERMAL SCIENCES, pp. 420–432, 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/30757.