Tungsten electrode erosion on DC horizontal short free arc in air
TL;DR: In this paper, the authors measured the temperature of DC horizontal short free arc between the tungsten electrodes in atmospheric air with a spectroscope and the electrode erosion, which was measured to be about 5500 K at 30, 50, 70 A current and 0.01 m plasma length.
About: This article is published in Vacuum.The article was published on 2004-04-19. It has received 8 citations till now. The article focuses on the topics: Electrode & Electric arc.
Citations
More filters
TL;DR: In this article, a numerical simulation model of a twin torch plasma arc at opposite electrodes was developed to elucidate high-efficiency heating using a twin-toron plasma arc, defined as Local Thermal Equilibrium (LTE) and calculated in Magneto-Hydro-Dynamic (MHD) equations.
12 citations
TL;DR: In this article, the arc length was measured using a plasma image processing on pictures taken with a high-speed video camera, and the average velocity of the anode was as fast as that of the cathode.
Abstract: Decreased electrode erosion is important to maintain an arc and reduce costs. Normally, a vacuum or rare gases such as argon and helium are used to prevent electrode erosion. However, associated equipment and its arrangement are expensive. If the anode attachment of the arc is moving, electrode erosion can be decreased even in an air atmosphere. This paper specifically addresses arc movement, especially the restrike phenomenon, in a rail-gun. The arc length was measured using a plasma image processing on pictures taken with a high-speed video camera. Thereby, the lengths and positions of the arc are determined over time. The average velocity of the anode is as fast as that of the cathode, even in restrike mode.
11 citations
Cites background from "Tungsten electrode erosion on DC ho..."
...Normally, anode erosion is greater than that of the cathode [3]....
[...]
TL;DR: In this paper, the authors compared the characteristics of a dual torch plasma arc used for hazardous waste treatment and operated at atmospheric pressure, and also compared with those of the multi-torch plasma arc and the single torch arc.
Abstract: In this paper, characteristics of a dual torch plasma arc used for hazardous waste treatment and operated at atmospheric pressure are studied, and also compared with those of the multi-torch plasma arc and the single torch plasma arc. The dual torch plasma arc is generated between the cathode and anode with argon as the working gas. The temperature distributions of the plasma arc are measured using a spectroscope and line pair method with the assumption of local thermodynamic equilibrium (LTE) for the DC arc current I = 100 A and argon flow rate Q = 15 slpm. The measurements show that the temperatures of the dual torch arc plasma in the regions near the cathode, the anode and the center point are 10,000 K, 11,000 K and 9,000 K, respectively. And the high temperature region of the multi torch plasma arc is of double or much wider size than that of a conventional dual torch plasma arc and single plasma torch. Based on the preceding studies, a dual torch plasma arc furnace is developed in this study. The measured gas temperature at the center region of the argon arc is about 11,000 K for the case of I = 200 A and Q = 30 slpm operated in atmosphere.
9 citations
TL;DR: In this article, a twin torch plasma arc with a rated current of 40 to 100 A is described such as arc mode, voltage as function of current and length, heating efficiency, and running cost for hazardous waste.
Abstract: The twin torch plasma arc has a higher temperature arc column. For that reason, it can generate high temperature and treat non-conducting material, even though it is a non-transfer type. Therefore, the twin torch plasma arc is a more effective device for treatment of hazardous waste. However, the arc mode is not easy to control in the twin torch plasma arc. In this paper, a twin torch plasma arc with a rated current of 40 to 100 A is described such as arc mode, voltage as function of current and length, heating efficiency, and running cost for hazardous waste. The high temperature region of the twin torch plasma arc is larger than that of a conventional single plasma torch. The plasma arc length can be changed as a function of the plasma gas flow rate. The arc voltage is also variable as a function of the current and plasma gas flow rate. The temperature of twin torch plasma was measured to be about 10000 K near the cathode and anode, and 8900 K at the center point between the electrodes at 100 A. The neutral bar received heat power of the amount of 280-500 W, and the fraction of the total power transferred to the neutral bar is 12-18%.
9 citations
TL;DR: In this paper, a portable twin-torch plasma arc furnace for waste treatment, thermal spraying torches, steam plasma torches, and surface treatment of low-pressure arc was developed.
Abstract: Thermal plasma and arc discharge have numerous useful characteristics related to their high temperature and intense radiation. Many applications have been developed. Recently, a portable twin-torch plasma arc furnace for waste treatment, thermal spraying torches, steam plasma torches, and surface treatment of low-pressure arc was developed. This paper describes the recent development of a portable application of thermal plasma and arc discharge. The portable device can treat wastes and perform thermal spraying and surface treatments on site. This technology is expected to become more attractive. © 2006 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
7 citations
References
More filters
TL;DR: In this paper, the principles are discussed and examples of waste treatment such as fly ash, asbestos, aluminum, municipal wastes, low level nuclear wastes, etc. by using DC arc discharge plasma are shown.
Abstract: The problem of the disposal of hazardous wastes has become very important in recent years. Plasma treatment is being developed and tested for incinerator ash, low level radioactive wastes, industrial and biomedical wastes, etc. by industrial companies and municipalities world wide. In this paper, the principles are discussed and examples of waste treatment such as fly ash, asbestos, aluminum, municipal wastes, low level nuclear wastes, etc. by using DC arc discharge plasma are shown.
72 citations
TL;DR: In this paper, the authors measured the radiation power emitted from a plasma torch as a function of the electric in-put power and found that the power increases steeply with the input power.
20 citations
TL;DR: The effect of the length of the plasma length on the characteristics of a DC argon plasma torch arc generated by a transfer-type plasma torch (ISET-PSA, Atlanta I (1995) 13) has been investigated in this article.
20 citations
TL;DR: In this paper, the authors measured the radiation power emitted from the Ar plasma torch, which increased in proportion to the 1.8-1.9th power of the current at 1, 2 cm of appearance plasma length.
Abstract: The plasma torch that can usually reduce the waste and dissolve the iron and so on has very useful characteristics. It is a kind of the stabilized arc plasma that can be easily controlled. It has been examined considering the influences or various parameters, such as the current, the gas flow-rate and the plasma length. In this paper, we measured the radiation power emitted from the Ar plasma torch. The radiation power increased in proportion to the 1.8-1.9th power of the current at 1, 2 cm of appearance plasma length. And it increased in proportion to the 0.2-0.4th power of the gas-flow rate between 4-20 NI/min. Then, we measured the temperature of the radiation spot collected by reflectors using the thermocouple. It increased in proportion to the 2.0-2.1th power of the current at 1 cm and 2 cm in the plasma length. Moreover, the total temperature is calculated as 16 860 K in a torus model. We proposed the treatment for the hazardous wastes using the highly intense radiation of Ar torch plasma collected by reflectors and concentrated by the lens. And, we proposed the plasma treatment of the high temperature and radiation power for the hazardous wastes by using the plasma torch. The plasma torch ordinary has the high temperature and plenty of radiation power. Therefore, when both of the characteristics are combined usefully, we can get the many more benefits; the in-put power is used little, hazardous wastes are treated by the high temperature and hazardous gas from the wastes is treated by the radiation power.
18 citations
TL;DR: In this article, a hollow cathode argon plasma instrument was applied to the decomposition of Dioxin in order to analyze the temperature and velocity distribution in the argon plasmas.
14 citations