Radiative heat transfer modeling of cavities with inhomogeneous participating media using Monte Carlo ray tracing method

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2022-1-31

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Dincer, Selim

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A Monte Carlo ray-tracing method is developed to solve radiative heat transfer in inhomogeneous participating media with three-dimensional complex enclosures. The study covers the application of the Monte Carlo method to view factor calculations, surface-to-surface heat exchange problems, and gray and non-gray participating media analysis. Firstly, the present method is validated against the analytical solutions to calculate the view factor of a simple cylindrical enclosure with varying height-radius ratios. Then, the accuracy of the Monte Carlo method in surface-to-surface radiative heat transfer problems is evaluated by calculating the hemispherical emittance of cylindrical cavities with and without diaphragm. In order to evaluate the accuracy of the developed method in emitting, absorbing, and isotropically scattering gray participating media, several three-dimensional geometries are examined, including a cubic enclosure, an L-shaped enclosure, and an elliptical enclosure. Monte Carlo predictions for radiative heat flux along the enclosure boundaries are calculated and compared with the previous studies. Finally, the Monte Carlo method is applied to a rectangular enclosure containing (i) isothermal pure water vapor, (ii) isothermal and an inhomogeneous mixture of water vapor and nitrogen. The statistical narrow band model is utilized to simulate the spectral-dependent properties of real gas in radiative heat transfer. Radiative heat flux across the surface and divergence of radiative heat flux along the enclosure is obtained and validated against the reference solutions. The predictions of the Monte Carlo method exhibit near-perfect agreement with previous studies, revealing that the present method is accurate and reliable for radiative heat transfer analysis in participating media.

Subject Keywords

Monte Carlo method, Radiative heat transfer, Participating media, Non-gray gas models, Narrow band models

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https://hdl.handle.net/11511/96260

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

S. Dincer, “Radiative heat transfer modeling of cavities with inhomogeneous participating media using Monte Carlo ray tracing method,” M.S. - Master of Science, Middle East Technical University, 2022.