There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

A front-tracking method for the computations of multiphase flow

A new molecular spectroscopic database for high-temperature modeling of the spectra of molecules in the gas phase is described. This database, called HITEMP, is analogous to the HITRAN database but encompasses many more bands and transitions than HITRAN for the absorbers H2O, CO2, CO, NO, and OH. HITEMP provides users with a powerful tool for a great many applications: astrophysics, planetary and stellar atmospheres, industrial processes, surveillance, non-local thermodynamic equilibrium problems, and investigating molecular interactions, to name a few. The sources and implementation of the spectroscopic parameters incorporated into HITEMP are discussed.

HITEMP, the high-temperature molecular spectroscopic database

Numerical Initial Value Problems in Ordinary Differential Equations

Oxy-fuel combustion technology for coal-fired power generation

1. Fundamentals of Thermal Radiation 2. Radiative Property Predictions from Electromagnetic Wave Theory 3. Radiative Properties of Real Surfaces 4. View Factors 5. Radiative Exchange Between Gray, Diffuse Surfaces 6. Radiative Exchange Between Partially-Specular Gray Surfaces 7. Radiative Exchange Between Nonideal Surfaces 8. Surface Radiative Exchange in the Presence of Conduction and Convection 9. The Equation of Radiative Transfer in Participating Media 10. Radiative Properties of Molecular Gases 11. Radiative Properties of Particulate Media 12. Radiative Properties of Semitransparent Media 13. Exact Solutions for One-Dimensional Gray Media 14. Approximate Solution Methods for One-Dimensional Media 15. The Method of Spherical Harmonics (PN-Approximation) 16. The Method of Discrete Ordinates (SN-Approximation) 17. The Zonal Method 18. The Treatment of Collimated Irradiation 19. The Treatment of Nongray Extinction Coefficients 20. The Monte Carlo Method for Thermal Radiation 21. Radiation Combined with Conduction and Convection 22. Inverse Radiative Heat Transfer A. Constants and Conversion Factors B. Tables for Radiative Properties of Opaque Surfaces C. Blackbody Emissive Power Table D. View Factor Catalogue E. Exponential Integral Functions F. Computer Codes Author Index Subject Index

Radiative heat transfer

Chapter 22 – inverse radiative heat transfer

Up to this point we have concerned ourselves with radiative heat transfer problems, where the necessary geometry, temperatures, and radiative properties are known, enabling us to calculate the radiative intensity and radiative heat fluxes in such enclosures. Such cases are sometimes called “direct” heat transfer problems. However, there are many important engineering applications where knowledge of one or more input parameters is desired that cause a certain radiative intensity field. For example, it may be desired to control the temperatures of heating elements in a furnace, in order to achieve a specified temperature distribution or radiative heat load on an object being heated. Or the aim may be to deduce difficult to measure parameters (such as radiative properties, temperature fields inside a furnace, etc.) based on measurements of radiative intensity or radiative flux. Such calculations are known as inverse heat transfer analyses.

Inverse Radiative Heat Transfer

The weighted-sum-of-gray-gases approach for radiative transfer in nongray participating media, first developed by Hottel in the context of the zonal method, has been shown to be applicable to the general radiative equation of transfer Within the limits of the weighted-sum-of-gray-gases model (nonscattering media within a black-walled enclosure), any nongray radiation problem can be solved by any desired solution method after replacing the medium by an equivalent small number of gray media with constant absorption coefficients Some examples are presented for isothermal media and media at radiative equilibrium, using the exact integral equations as well as the popular P-1 approximation for the equivalent gray media solutions The results demonstrate the equivalency of the method with the quadrature of spectral results, as well as the tremendous computer times savings (by a minimum of 95 percent) that are achieved

The weighted-sum-of-gray-gases model for arbitrary solution methods in radiative transfer

A new Full-Spectrum Correlated-κ Distribution has been developed, which provides an efficient means for accurate radiative transfer calculations in absorbing/emitting molecular gases. The Full-Spectrum Correlated-κ Distribution can be used together with any desired solution method to solve the radiative transfer equation for a small number of spectral absorption coefficients, followed by numerical quadrature. It is shown that the Weighted-Sum-of-Gray-Gases model is effectively only a crude implementation of the Full-Spectrum Correlated-κ Distribution approach. Within the limits of the Full-Spectrum Correlated-κ Distribution model (i.e., an absorption coefficient obeying the so-called scaling approximation), the method is exact. This is demonstrated by comparison with line-by-line calculations for a one-dimensional CO 2 -N 2 gas mixture as well as a two-dimensional CO 2 -H 2 O-N 2 gas mixture with varying temperature and mole fraction fields

https://eng.ucmerced.edu/people/mmodest/portal/publications/papers/fskjht.pdf

Michael F. Modest

Papers

Radiative heat transfer

Chapter 22 – inverse radiative heat transfer

Inverse Radiative Heat Transfer

The weighted-sum-of-gray-gases model for arbitrary solution methods in radiative transfer

The Full-Spectrum Correlated-k Distribution for Thermal Radiation From Molecular Gas-Particulate Mixtures