Date of download: 10/9/2017 Copyright © ASME. All rights reserved. From: Influence of Index of Refraction and Particle Size Distribution on Radiative Heat Transfer in a Pulverized Coal Combustion Furnace J. Heat Transfer. 2017;139(4):042702-042702-8. doi:10.1115/1.4035205 Figure Legend: Refractive index for ash (left) and coal (right) and efficiencies calculated by Mie theory for two different particle sizes and different refractive indices. Gray shaded area denotes the blackbody radiation according to Planck for T = 1700 K to highlight the spectral range of interest for PCC. Solid lines correspond to Dp=1 μm, dash-dotted lines to Dp=10 μm and dashed lines to Dp=40 μm.

Date of download: 10/9/2017 Copyright © ASME. All rights reserved. From: Influence of Index of Refraction and Particle Size Distribution on Radiative Heat Transfer in a Pulverized Coal Combustion Furnace J. Heat Transfer. 2017;139(4):042702-042702-8. doi:10.1115/1.4035205 Figure Legend: Influence of the complex and the real part of the refractive index m on the scattering (black lines) and absorption (gray lines) efficiencies. Ash particles on the left and coal particles on the right. Reference values are m = 1.6 − i0.3 (coal) m = 1.6 − i0.01 (ash).

Date of download: 10/9/2017 Copyright © ASME. All rights reserved. From: Influence of Index of Refraction and Particle Size Distribution on Radiative Heat Transfer in a Pulverized Coal Combustion Furnace J. Heat Transfer. 2017;139(4):042702-042702-8. doi:10.1115/1.4035205 Figure Legend: Radiative source term for cases of type 1 with a cylinder diameter of 12 m and four different complex indices of refraction. For ash, the combined data, Refs. [17–19] (see Table 1), is used for the complex index of refraction.

Date of download: 10/9/2017 Copyright © ASME. All rights reserved. From: Influence of Index of Refraction and Particle Size Distribution on Radiative Heat Transfer in a Pulverized Coal Combustion Furnace J. Heat Transfer. 2017;139(4):042702-042702-8. doi:10.1115/1.4035205 Figure Legend: Wall fluxes for cases of type 1 with four different complex indices of refraction. For ash, the combined data, Refs. [17-19] (see Table 1), is used for the complex index of refraction.

Date of download: 10/9/2017 Copyright © ASME. All rights reserved. From: Influence of Index of Refraction and Particle Size Distribution on Radiative Heat Transfer in a Pulverized Coal Combustion Furnace J. Heat Transfer. 2017;139(4):042702-042702-8. doi:10.1115/1.4035205 Figure Legend: (a) Radiative source term for a type 2 case with a cylinder diameter of 12 m and (b) wall fluxes for type 2 cases. The applied indices of refraction are listed in Table 1.

Date of download: 10/9/2017 Copyright © ASME. All rights reserved. From: Influence of Index of Refraction and Particle Size Distribution on Radiative Heat Transfer in a Pulverized Coal Combustion Furnace J. Heat Transfer. 2017;139(4):042702-042702-8. doi:10.1115/1.4035205 Figure Legend: Sensitivity to the complex index of refraction of coal particles expressed as the relative difference between the maximum result and the minimum result for (a) type 1 cases and (b) type 2 cases. Black lines is the wall flux, and gray lines is the source term at the center of the cylinder for type 1 cases and the average source term for type 2 cases.

Date of download: 10/9/2017 Copyright © ASME. All rights reserved. From: Influence of Index of Refraction and Particle Size Distribution on Radiative Heat Transfer in a Pulverized Coal Combustion Furnace J. Heat Transfer. 2017;139(4):042702-042702-8. doi:10.1115/1.4035205 Figure Legend: (a) Radiative source term for a type 1 case considering a size distribution for the coal particles compared to the use of a single mean diameter, D32, Eq. (3). (b) Relative error caused by an approximation of a particle size distribution with a mean, D32, particle diameter.