Application of the weighted-sum-of-gray-gases model for media composed of arbitrary concentrations of H 2 O, CO 2 and soot

Numerical simulations of the radiative transfer in a 2D axisymmetric turbulent non-premixed methane–air flame using up-to-date WSGG and gray-gas models

“…To do that, it is taking into account a WSGG model with correlations obtained for a fixed ratio between the concentrations of the participating species [16], a WSGG model with correlations that allow variations in the concentration ratios [17], and a sophisticated gray-gas model which allows temperature dependence for the absorption coefficient [18], both based on HITEMP 2010 data [14]. …”

“…There has been some recent works that propose an additional dimension to the correlations, in addition to the temperature dependence, to allow variations in the concentration ratios [13,15,32]. A different approach was proposed in [17], which obtained correlations separately for H 2 O and CO 2 , and then combined those correlations to solve mixtures with arbitrary ratios in the concentration.…”

“…According to [17], the weighting factor a j can be interpreted as the probability that the energy of the blackbody is emitted in the regions of the spectrum where the absorption coefficient is κ j . Therefore, the probability that the gray-gas absorption coefficient of the mixture is the sum of a given combination of the gray-gas absorption coefficients of the components will be equal to the product of their respective probabilities.…”

“…Recently, HITEMP 2010 [14] was released as a major improvement of previous versions, expanding the number of transition lines for H 2 O and CO 2 , and also allowing for application in temperatures up to 4000 K. In recent works, Kangwanpongpan et al [15] considered the determination and evaluation of new correlations for the WSGG model, fitted from emittance charts calculated from the up-to-date HITEMP 2010 database, to predict the radiative transfer in gases under oxyfuel conditions, while Dorigon et al [16] generated correlations for typical ratios of partial pressures of the products of combustion of methane and fuel oil. Cassol et al [17] developed new coefficients for the WSGG based on HITEMP 2010 but with a methodology that provides separate coefficients for H 2 O and CO 2 , together with a methodology that allows the mixture of any concentration of those chemical species. Cassol et al [18] fitted temperature-dependent coefficients for a GG model also based on HITEMP 2010 data.…”

“…This study presents a numerical RANS (Reynolds Average Navier-Stokes) simulation of turbulent non-premixed methane-air flame in a cylindrical combustion chamber taking into account radiation effect of non-gray gases by means of different WSGG [16,17] and GG [18] correlations both generated from HITEMP 2010 database [14] and including TRI [19], with the objective of evaluating the influence of the different radiation models on the overall thermal behavior of the combustion chamber. For evaluation of the proposed solution, the case described in [20] was studied, since detailed spatial measurements are available for the main gas species concentrations and for the temperature field.…”