A Hybrid Wavenumber Selection Scheme for Line-By-Line Photon Monte Carlo Simulations in High-Temperature Gases

2013 ◽  
Vol 135 (8) ◽  
Author(s):  
Tao Ren ◽  
Michael F. Modest
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Method ◽  
Radiative Heat ◽  
Previous Method ◽  
Selection Scheme ◽  
Combustion Gases ◽  
The Monte Carlo Method ◽  
Time Requirements ◽  
Original Scheme ◽  
Wavenumber Selection

Recently, it has become possible to conduct line-by-line (LBL) accurate radiative heat transfer calculations in spectrally highly nongray combustion systems using the Monte Carlo method. LBL accuracy, in principle, adds little to the computational load as compared to gray calculations. However, when employing the Monte Carlo method, the original scheme for choosing appropriate emission wavenumbers for statistical photon bundles is numerically expensive. An improved wavelength selection scheme has been applied to hypersonic plasmas for Monte Carlo solvers. However, directly applying this improved scheme to combustion gases may cause significant errors. In this paper, a hybrid scheme for wavenumber selection is proposed, significantly decreasing CPU requirements compared to previous work. The accuracy of the new method is established and its time requirements are compared against the previous method.

Line-by-Line Random-Number Database for Monte Carlo Simulations of Radiation in Combustion System

2018 ◽  
Vol 141 (2) ◽  
Author(s):  
Tao Ren ◽  
Michael F. Modest
Keyword(s):  
Heat Transfer ◽  
Monte Carlo ◽  
Monte Carlo Method ◽  
Radiative Heat ◽  
Random Number ◽  
Test Cases ◽  
Combustion System ◽  
Absorption Coefficients ◽  
One Dimensional ◽  
The Monte Carlo Method

With today's computational capabilities, it has become possible to conduct line-by-line (LBL) accurate radiative heat transfer calculations in spectrally highly nongray combustion systems using the Monte Carlo method. In these calculations, wavenumbers carried by photon bundles must be determined in a statistically meaningful way. The wavenumbers for the emitting photons are found from a database, which tabulates wavenumber–random number relations for each species. In order to cover most conditions found in industrial practices, a database tabulating these relations for CO2, H2O, CO, CH4, C2H4, and soot is constructed to determine emission wavenumbers and absorption coefficients for mixtures at temperatures up to 3000 K and total pressures up to 80 bar. The accuracy of the database is tested by reconstructing absorption coefficient spectra from the tabulated database. One-dimensional test cases are used to validate the database against analytical LBL solutions. Sample calculations are also conducted for a luminous flame and a gas turbine combustion burner. The database is available from the author's website upon request.

The Monte Carlo Method in Radiative Heat Transfer

1998 ◽  
Vol 120 (3) ◽  
pp. 547-560 ◽  
Author(s):  
J. R. Howell
Keyword(s):  
Heat Transfer ◽  
Monte Carlo ◽  
Monte Carlo Method ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Hybrid Methods ◽  
Participating Media ◽  
Practical Applications ◽  
Monte Carlo Techniques ◽  
The Monte Carlo Method

The use of the Monte Carlo method in radiative heat transfer is reviewed. The review covers surface-surface, enclosure, and participating media problems. Discussion is included of research on the fundamentals of the method and on applications to surface-surface interchange in enclosures, exchange between surfaces with roughness characteristics, determination of configuration factors, inverse design, transfer through packed beds and fiber layers, participating media, scattering, hybrid methods, spectrally dependent problems including media with line structure, effects of using parallel algorithms, practical applications, and extensions of the method. Conclusions are presented on needed future work and the place of Monte Carlo techniques in radiative heat transfer computations.

Sign in / Sign up

Export Citation Format

Share Document