Net emission coefficient of CO₂-Cu thermal plasmas: role of copper and molecules.

Investigation on the Influence of Gas Pressure on CO2 Arc Characteristics in High-Voltage Gas Circuit Breakers

“…The thermodynamic and transport properties of CO 2 are taken from the study of Tanaka [6]. The net emission coefficient of CO 2 is taken from the study of Billoux [7]. The The commercial computational software ANSYS FLUENT is used to model the circuit breaker and solve the governing equations.…”

On the order reduction of the radiative heat transfer model for the simulation of plasma arcs in switchgear devices

“…Broadening effects due to pressure are also important as they contribute to a spread of the absorption lines over the nearby frequencies. Physical models to capture such complex absorption spectra have been proposed in the literature, [4,16,3,8]. Moreover, databases of experimentally measured absorption data for several mixtures in specific frequency bands are available, typically for relatively low temperatures [21].…”

“…Indeed, the topic of modeling accurately and/or measuring the absorption spectrum of a given gas as a function of temperature and pressure (i.e. to compute the base data D) is by itself an important and active research area [4,16,3,8], however it is outside the scope of this work, which is focused on the simplification of the FOM into a computationally tractable model. On the other hand, the method presented in this paper does not depend on the specific absorption spectrum, i.e.…”

“…The course of e(T, ν) is illustrated in Figure 5. By inserting the spectral emissivity (8) in equation (2), the radiated heat intensity for each frequency value ν i , i = 1, . .…”

“…The mentioned approaches have the advantage of being quite simple to implement, however in principle one should optimally choose ad-hoc different bands and averaged absorption coefficients as a function of pressure, temperature and chemical composition of the considered medium, since the radiation parameters are affected by all these aspects. If the bands and/or the averaged absorption coefficients are not chosen in an appropriate way, the model accuracy is worse and more bands are needed to improve it, resulting in a relatively large number of bands (6)(7)(8)(9)(10) in order to achieve accurate results with respect to the original, large-scale model. Hence, this procedure can be time consuming, not trivial to carry out in a systematic way, and ultimately suboptimal in terms of complexity/accuracy compromise.…”