Artículos de revistas
A Theoretical And Experimental Investigation Of Copper Electrode Erosion In Electric Arc Heaters: Iii. Experimental Validation And Prediction Of Erosion
Registro en:
Journal Of Physics D: Applied Physics. , v. 30, n. 17, p. 2421 - 2430, 1997.
223727
10.1088/0022-3727/30/17/008
2-s2.0-0031558466
Autor
Sharakhovsky L.I.
Marotta A.
Borisyuk V.N.
Institución
Resumen
Experimental results are presented on copper-cathode erosion for magnetically driven arcs in air, for currents in the range 0.025-1 kA, magnetic induction values 0.03-0.24 T, arc velocities 19.3-344 m s-1 and electrode surface temperatures 300-1073 K. From experimental data we obtained the important characteristic parameters for the copper-cathode's erosion process; namely the effective enthalpy of electrode material ablation in the arc spot, hef, and the specific microerosion value, g0. The experiments demonstrated that, just like the near-cathode thermal volt equivalent U, the arc spot current density j is also a monotonic ascending function of the magnetic field strength. We have shown a good agreement between the theory and the experimental data for a wide range of arc-heater operating regimes. A mathematical analysis and diagrams are provided for predicting the best conditions for an arc heater to work with the minimum erosion level. The minimum erosion is shown to depend on the temperature attained by the electrode and on the degree of influence of the gas velocity on the electrode temperature. It is predicted that the erosion decreases with increasing arc velocity, then stabilizes at a given minimum level and then increases as one increases the value of the arc velocity. 30 17 2421 2430 Marotta, A., Sharakhovsky, L.I., A theoretical and experimental investigation of copper electrode erosion in electric arc heaters: I. The thermophysical model (1996) J. Phys. D: Appl. Phys., 29, pp. 2395-2403 Sharakhovsky, L.I., Marotta, A., Borisyuk, V.N., A theoretical and experimental investigation of copper electrode erosion in electric arc heaters: II. Experimental determination of arc spot parameters (1997) J. Phys. D: Appl. Phys., 30, pp. 2018-2025 Mikheev, M., Fundamentals of Heat Transfer, , Moscow: Mir Touloukian, Y.S., Powell, R.W., Ho, C.Y., Klements, P.G., (1970) Thermal Conductivity of Metallic Elements and Alloys, 1. , New York: IFI/Plenum Touloukian, Y.S., Powell, R.W., Ho, C.Y., Klements, P.G., (1973) Diffusivity, 10. , New York: IFI/Plenum Rakhovskii, V.I., Experimental study of the dynamics of cathode spots development (1976) IEEE Trans. Plasma Sci., 4, pp. 81-102 Rakhovskii, V.I., Electrode erosion in a constricted discharge (1975) Izv. Sibirckogo Otdelenija Akad. Nauk SSSR, Ser. Tekhn. Nauk, 1, pp. 11-27. , in Russian Anshakov, A.S., Timoshevsky, A.N., Urbakh, E.K., Erosion of copper cylindrical cathode in air (1988) Izv. Sibirckogo Otdelenija Akad. Nauk SSR, Ser. Tekhn. Nauk, 2, pp. 65-68. , in Russian Szente, R.N., Munz, R.J., Drouet, M.G., The effect of low concentrations of a polyatomic gas in argon on erosion on copper cathodes in a magnetically rotated arc (1987) Plasma Chem. Plasma Processing, 7, pp. 349-364 Sharakhovsky, L.I., Experimental investigation of an electric arc motion in annular ventilated gap under the action of electromagnetic force (1971) J. Eng. Phys., 20, pp. 306-313 Koroteev, A.S., Mironov, V.M., Svirchuk, J.S., (1993) Plasmotrons - Design, Characteristics, Calculations, , (Moscow: Mashinostroenie) (in Russian) Teste, P., Andlauer, R., Leblanc, T., Chabrerie, J.P., Pasquini, P., Contribution to the study of cathode erosion of plasma torches (1994) High Temp. Chem. Processes, pp. 399-407 Teste, P., Leblanc, T., Chabrerie, J.P., Study of the arc root displacement and three-dimensional modelling of the phenomena occurring in a hollow cathode submitted to an electric moving arc (1995) J. Phys. D: Appl. Phys., 28, pp. 888-898 Anshakov, A.S., Dautov, G.U., Mustafin, G.M., Petrov, A.P., Study of pulsations in plasma torch with self-establishing arc length (1967) J. Appl. Mech. Eng. Phys., pp. 161-166. , in Russian Sharakhovsky, L.I., Kostin, N.A., Vortex flows in electric arc heaters (1984) Heat Transfer Sov. Res., 16, pp. 126-140 Szente, R.N., Munz, R.J., Drouet, M.G., Effect of the arc velocity on the cathode erosion rate in argon-nitrogen mixtures (1987) J. Phys. D: Appl. Phys., 20, pp. 754-756 Szente, R.N., Munz, R.J., Drouet, M.G., Electrode erosion in plasma torches with gas vortex driven arcs (1991) Proc. 10th Int. Symp. on Plasma Chemistry (Bochum, Germany, 4-9 August 1991), pp. 1.3-141-1.3-147. , ed U Ehlemann, H G Lergon and K Wiesenann