Comparison of Mean Methods Suitable for Radiation Properties Evaluation in CO2/O2 Plasma at Various Pressures

Comparison of Mean Methods Suitable for Radiation Properties Evaluation in CO2/O2 Plasma at Various Pressures

Paper in proceedings outside WoS and Scopus

Evaluation of a radiation energy transfer plays a very important role in numerical simulations of thermal plasma. Unfortunately, a precise radiation evaluation would demand unacceptably huge computation power due to a very complex nature of a radiation propagation and spectral dependence. A simplified methods are thus generally used for both spectral and spatial part of the radiation transfer evaluation with methods such as Net Emission Coefficients (NEC), Mean Absorption Coefficients (MAC), P1 approximation, Discrete Ordinates Method (DOM), k-bands discretization etc. In this contribution, we focus only on a very small part of the entire simulation process, namely on the radiation transfer in the CO2/O2 thermal plasma mixture and its accurate representation in relation to the gas pressure. We show, that for the pressure above 10 bars the Rosseland mean absorption coefficient is the best method while at the low pressure limit the line limited Planck mean absorption coefficient exhibits much better accuracy, especially in the case of correctly estimated characteristic plasma absorption length. Unfortunately, neither method offers particularly high accuracy at intermediate pressures around 10 bars, where some other mean methods might be considered.

Evaluation of a radiation energy transfer plays a very important role in numerical simulations of thermal plasma. Unfortunately, a precise radiation evaluation would demand unacceptably huge computation power due to a very complex nature of a radiation propagation and spectral dependence. A simplified methods are thus generally used for both spectral and spatial part of the radiation transfer evaluation with methods such as Net Emission Coefficients (NEC), Mean Absorption Coefficients (MAC), P1 approximation, Discrete Ordinates Method (DOM), k-bands discretization etc. In this contribution, we focus only on a very small part of the entire simulation process, namely on the radiation transfer in the CO2/O2 thermal plasma mixture and its accurate representation in relation to the gas pressure. We show, that for the pressure above 10 bars the Rosseland mean absorption coefficient is the best method while at the low pressure limit the line limited Planck mean absorption coefficient exhibits much better accuracy, especially in the case of correctly estimated characteristic plasma absorption length. Unfortunately, neither method offers particularly high accuracy at intermediate pressures around 10 bars, where some other mean methods might be considered.

radiation transfer; CO2/O2

radiation transfer; CO2/O2

KLOC, P.; AUBRECHT, V.; BARTLOVÁ, M.; GORTSCHAKOW, S.; ROBIN-JOUAN, P.

2024

10.09.2023

Proceedings XXIII International Conferenceon Gas Discharges and their Applications

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