scholarly journals A MULTI-SCALE FULL-SPECTRUM CORRELATED-k DISTRIBUTION FOR RADIATIVE HEAT TRANSFER IN INHOMOGENEOUS GAS MIXTURES

2001 ◽  
Author(s):  
Hongmei Zhang
Keyword(s):  
Heat Transfer ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Gas Mixtures ◽  
Full Spectrum ◽  
Multi Scale ◽  
Inhomogeneous Gas

Multi-Scale Full-Spectrum k-Distribution Method for Radiative Transfer in Inhomogeneous Gas Mixtures With Wall Emission

2005 ◽  
Author(s):  
Liangyu Wang ◽  
Michael F. Modest
Keyword(s):  
Heat Transfer ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Inhomogeneous Media ◽  
Full Spectrum ◽  
Distribution Method ◽  
Multi Scale ◽  
Original Distribution ◽  
Distribution Scheme ◽  
Inhomogeneous Gas

The multi-scale full-spectrum k-distribution (MSFSK) method has become a promising method for radiative heat transfer in inhomogeneous media. In this paper an original distribution scheme is proposed to extend the MSFSK’s ability in dealing with boundary wall emission. This scheme pursues the overlap concept of the MSFSK method and requires no changes in the original MSFSK formulation. A boundary emission overlap coefficient is introduced and two approaches of evaluating the coefficient are outlined. The distribution scheme is evaluated and the two approaches are compared by conducting sample calculations for radiative heat transfer in strongly inhomogeneous media using both the MSFSK method and the line-by-line method.

A Hybrid Multi-Scale Full-Spectrum k-Distribution Method for Radiative Transfer in Inhomogeneous Gas Mixtures

2005 ◽  
Author(s):  
Liangyu Wang ◽  
Michael F. Modest
Keyword(s):  
Radiative Heat ◽  
Single Species ◽  
Gas Mixtures ◽  
Great Accuracy ◽  
New Method ◽  
Full Spectrum ◽  
Participating Media ◽  
Distribution Method ◽  
Multi Scale ◽  
Inhomogeneous Gas

A new full-spectrum k-distribution (FSK) method has been developed, which integrates the advantage of the multi-group FSK method in dealing with temperature inhomogeneities for single-species media with the advantages of the multi-scale FSK method in dealing with partial pressure inhomogeneities for gas mixtures. The new method can achieve great accuracy for radiative heat tranfer calculations in participating media with inhomogeneities in both temperature and gas concentrations. The mathematical development of the new method is described, and several sample calculations are performed to demonstrate the accuracy the new method by comparison with line-by-line calculations.

Reverse Monte-Carlo Ray-Tracing Method Combined With Full-Spectrum K-Distribution Method for Radiative Heat Transfer

2008 ◽  
Author(s):  
Xiaojing Sun ◽  
Philip J. Smith
Keyword(s):  
Heat Transfer ◽  
Monte Carlo ◽  
Ray Tracing ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Radiative Transfer Equation ◽  
Computational Effort ◽  
Simulation Methods ◽  
Full Spectrum ◽  
Distribution Method

Accurate prediction of radiative heat transfer plays a key role in many high temperature applications, such as combustion devices and fires. Among various simulation methods, the Monte-Carlo Ray-Tracing (MCRT) has the advantage of solving the radiative transfer equation (RTE) for real gas mixtures with almost no approximations; however, it has disadvantage of requiring a large computational effort. The MCRT method can be carried out with either the Forward MCRT or the Reverse MCRT, depending on the direction of ray tracing. The RMCRT method has advantages over the FMCRT method in that it uses less memory, and in a domain decomposition parallelization strategy, it can explicitly obtain solutions for the domain of interest without the need for the solution on the entire domain.

Radiative Heat Transfer in High-Pressure Laminar Hydrogen-Air Diffusion Flames Using Spherical Harmonics and K-Distributions

2012 ◽  
Author(s):  
Jian Cai ◽  
Shenghui Lei ◽  
Adhiraj Dasgupta ◽  
Michael F. Modest ◽  
Dan C. Haworth
Keyword(s):  
Heat Transfer ◽  
High Pressure ◽  
Water Vapor ◽  
Spherical Harmonics ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Diffusion Flames ◽  
Transport Equations ◽  
Full Spectrum ◽  
Air Jet

Radiative heat transfer is studied numerically for high-pressure laminar H2-air jet diffusion flames, with pressure ranging from 1 to 30 bar. Water vapor is assumed to be the only radiatively participating species. A full spectrum k-distribution spectral model is used. Narrowband k-distributions of water vapor are calculated and databased from the HITEMP 2010 database, which claims to retain accuracy up to 4000K. The full-spectrum k-distributions are assembled from their narrowband counterparts to yield high accuracy with little additional computational cost. The radiative transfer equation (RTE) is solved using various spherical harmonics methods, such as P1, simplified P3 (SP3) and simplified P5 (SP5). The resulting partial differential equations as well as other transport equations in the laminar diffusion flames are discretized with the finite-volume method in OpenFOAM. Differential diffusion effects which are important in laminar hydrogen flames are also included in the scalar transport equations. It was found that peak flame temperature becomes less sensitive to radiation at higher pressure, and that radiation causes cooling in the downstream region. Differences between the three spherical harmonics RTE solver were found negligible below 5 bar.

SLMB Modeling of the Full Spectrum Cumulative k-Distribution of H2O

2009 ◽  
Author(s):  
Fre´de´ric Andre´ ◽  
Rodolphe Vaillon
Keyword(s):  
Heat Transfer ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Radiative Properties ◽  
Comprehensive Description ◽  
Full Spectrum ◽  
Reliable Technique ◽  
Gaseous Media ◽  
Energy Exchanges ◽  
Atmospheric Heat

Radiative heat transfer is significant in many applications involving energy exchanges in gaseous media, such as combustion in engines or furnaces, atmospheric heat balances,.. The Line-By-Line (LBL) approach is the most reliable technique to determine the radiative properties of gases but is rarely used in radiative transfer simulations due to the associated prohibitive computational requirements. Approximate models are favored for such calculations. A comprehensive description of these existing methodologies can be found in Refs. [1, 2].

A Parametric Case Study in Radiative Heat Transfer Using the Reverse Monte-Carlo Ray-Tracing With Full-Spectrum k-Distribution Method

2009 ◽  
Vol 132 (2) ◽  
Author(s):  
Xiaojing Sun ◽  
Philip J. Smith
Keyword(s):  
Heat Transfer ◽  
Monte Carlo ◽  
Ray Tracing ◽  
Radiative Heat Transfer ◽  
Radiative Heat ◽  
Reverse Monte Carlo ◽  
Full Spectrum ◽  
Distribution Method ◽  
Mesh Resolution ◽  
Emitting Media

A combined method of reverse Monte-Carlo ray-tracing with full-spectrum k-distribution (FSK) for computing the radiative heat transfer is applied to an extreme nonhomogeneous case (both temperature and gas mixture composition vary with positions) with an absorbing, emitting media. The parameter studies of the scaled FSK (FSSK) and correlated FSK (FSCK) methods for the case, such as g point resolution, mesh resolution, reference states, and integration quadratures, are carried out. The results from the FSSK and FSCK are only affected by the chosen reference states and are not sensitive to other parameters.

Sign in / Sign up

Export Citation Format

Share Document