The objective of this work is to compare the accuracy of several approximate models of radiative properties for the prediction of radiative transfer in air arc plasma at the temperatures in the range of 300 - 25 000 K and the pressure of 0.1 MPa. Calculated absorption coefficients are used to generate the parameters of different models. The radiative transfer inside the cylindrically symmetrical air plasma with prescribed temperature profile was studied. The equation of radiative transfer was solved using the P1 and SP3 approximations, calculated radiative source term in the energy equation (net emission) was compared with results obtained by spectral integration.
The aim of this paper is to evaluate radiation properties of air arc plasmas with various admixtures of copper vapours. The first order of the method of spherical harmonics (P<sub>1</sub>-approximation) has been used as the way to solve the equation of radiation transfer. Calculations of the absorption coefficients for a thermal plasma have been performed as a function of the temperature and the frequency. The frequency variable in the equation of transfer was handled by means of multigroup method. Methods for prediction of the average absorption coefficients were described and compared in detail. The net emission coefficients have been determined for comparison.
Abstract:The objective of the paper consists of a theoretical prediction of radiative heat transfer in arc plasmas of SF 6 (sulphur hexafluoride) with various admixtures of copper vapours. The P1-approximation was used as a mathematical tool. Due to the very complicated frequency dependence of absorption coefficients, the Planck and Rosseland mean absorption coefficients have been derived from the calculated absorption spectrum. The main radiation quantities (radiation intensity, radiation flux density and its divergence -net emission) have been determined in cylindrical arc plasmas for several model temperature profiles. Contribution to the net emission of copper admixtures is discussed. Conclusions have been made concerning validity and utilization of various absorption means.
The first order of the method of spherical harmonics (P1-approximation) has been used to evaluate the radiation properties of arc plasmas of various mixtures of SF6 and PTFE ((C2F4)n, polytetrafluoroethylene) in the temperature range (1000 ÷ 35 000) K and pressures from 0.5 to 5 MPa. Calculations have been performed for isothermal cylindrical plasma of various radii (0.01 ÷ 10) cm. The frequency dependence of the absorption coefficients has been handled using the Planck and Rosseland averaging methods for several frequency intervals. Results obtained using various means calculated for different choices of frequency intervals are discussed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.