Thermodynamic Properties and Viscosity of High Temperature Argon Mixed with Iron Vapor

Abstract

Thermodynamicproperties such as enthalpy and specific heat, and viscosity of different compositions of argon-iron mixture gases are calculated under the assumption of local thermal equilibrium for a temperature range of 2,500K to 30,000K.The enthalpy decreases basically with increasing iron vapor content, however increases in the temperature range between 5,000 and 14,000K due to the ionization of iron atoms around 7,000K. The specific heat changes complexly with temperature having several peaks corresponding to the ionization of iron and argon atoms and their ions. The viscosity decreases with increasing iron vapor content above the temperature range of 6,000K due to the iron ions, which have a relatively large coulombic cross section. Increasing pressure causes the enthalpy to be decreased, however the viscosity to be increased. This result comes from the upward shift of temperature region in which the ionization reactions proceed efficiently.

Modelling of time dependent plasma plume induced during laser welding

“…The viscosity and the thermal conductivity coefficients of iron vapour were taken from [9]. Although the Wilke estimation is not very accurate for plasma it has been found that in our case the values obtained by Fluent are in fair agreement with the values obtained from more rigorous calculations [10]. Similar agreement has been found in the case of thermodynamic properties.…”

Thermodynamic and transport properties of argon‐alumina mixture

“…The validity of the calculation methods and the average cross sections regarding Ar has already been confirmed through the comparison of our results on the electrical and thermal conductivity and viscosity of pure Ar with the reported values of calculation and experiment [11,12]. But in the present paper, we used the rigid sphere model for some interactions.…”

“…The validity of the method has already been confirmed by comparison of reported results on the specific enthalpy and specific heat of pure Ar and our calculation results [11]. Also, we used all possible new data on molecular constants.…”

“…The calculation methods are the same as in previous papers [11,12], except for neglect of the internal thermal conductivity because of its small contribution to the total thermal conductivity.…”

The spectroscopic determination of the temperature and copper vapour concentration for arc jets of 50 kA ac arc in the long gap

“…The calculation method was the same as that used in [5] and [7] and an outline of the method is provided in an appendix to this paper. The particle composition of high-temperature air contaminated with copper vapour (0.1 MPa) was obtained from [10]. Figure 5 shows the calculated results of the particle composition [10].…”