As the flight speeds of aircraft are increased above Mach 5, efficient methods of propulsion are needed. Scramjets may be a solution to this problem. Supersonic combustion is one of the main challenges involved in the operation of a Scramjet engine. In general, both an igniter and a flameholder are needed to achieve and maintain supersonic combustion. The current work examines a plasma torch-strut combination as an igniter-flameholder. The plasma torch-strut combination was tested in the Virginia Tech unheated supersonic wind tunnel at Mach 2.4. Pressure and temperature sampling, filtered photography, and spectroscopic measurements were used to compare different test cases. These results provide both qualitative and quantitative results on how the combination responds to changes in the mass flow rate of fuel and the power to the plasma torch. The key conclusions of the work were the following: 1. Tests showed that an exothermic reaction takes place. 2. The amount of heat release increases with an increase in the mass flow rate of fuel. 3. The plasma torch-fuel injector interaction caused the heat release to be well above the tunnel floor and sometimes off the strut centerline 4. One change in the fuel injector pattern caused more temperature rise near the floor of the tunnel. 5. The flow penetration height of the plasma torch alone was reduced by the fuel-plasma torch interaction. 6. Moving the strut upstream reduced the measured temperature rise at a fixed downstream location, but increased the penetration height of the plasma torch. 7. The computed heat release was found to be small compared to the potential heat release from all the fuel burning. 8. The amount of temperature rise caused by the fuel is not greatly affected by the power to the plasma torch. / Master of Science

The oscillating plasma torch is proposed as a potential device that will produce an oscillating shock and resulting control of the supersonic combustion process. This research will capitalize on previous results [Gallimore, 1998] which indicate that the plasma torch oscillations originate from the inherent oscillations of the voltage applied to the torch. The aim of this research is to thoroughly investigate the oscillation behavior of the plasma torch with the plan of ultimately controlling the oscillation at chosen frequencies. A modulating power system used for dynamic control of the plasma torch oscillation was designed and tested in quiescent conditions (no flow), Mach 2.4 cold supersonic flow, and Mach 2 heated supersonic flow conditions. The oscillating plasma torch used nitrogen feedstock and was operated over a frequency range of 2Hz- 4kHz. A dynamic torch model using the hybrid Mayr-Cassie electric arc model was developed to predict the plasma torch electric arc response at appropriate frequencies for interaction with supersonic combustion. In quiescent conditions, the dynamic response of the plasma torch power system and plasma jet were characterized using signal processing techniques and high speed video imaging. High speed Schlieren images were used to determine the behavior of the oscillating plasma jet in Mach 2.4 cross flow and its influence on the induced shock structure. The unsteady nitrogen-fed torch was integrated with the flush walled 4-hole aerodynamic ramp injector using hydrogen and hydrocarbon fuels at the University of Virginia Aerospace Research Lab (ARL) heated Mach 2 supersonic flow. Unsteady pressure variations from the oscillating shock produced by the plasma torch were recorded using recess-mounted Kulite pressure transducers. Also, measurements of the static pressure of the combustion produced by the oscillating plasma torch were obtained. The oscillating torch system performed well over a range of different flow conditions. It will enable active control input to the combustion process. The controllable unsteady blockage might provide a type shock interaction needed to increase turbulence and mixing augmentation [Kumar, et al. 1987]. / Master of Science

A newly designed liquid fuel (kerosene) aeroramp injector/plasma igniter was tested in cold flow using the Virginia Tech supersonic wind tunnel at Mach 2.4. The liquid fuel (kerosene) injector is flush wall mounted and consists of a 2 hole aeroramp array of impinging jets that are oriented in a manner to improve mixing and atomization of the liquid jets. The two jets are angled downstream at 40 degrees and have a toe-in angle of 60 degrees. The plasma torch used nitrogen and air as feedstocks and was placed downstream of the injector as an ignition aid. First, schlieren and shadowgraph photographs were taken of the injector flow to study the behavior of the jets, shape of the plume, and penetration of the liquid jet. The liquid fuel aeroramp was found to have better penetration than a single, round jet at 40 degrees. However, the liquid fuel aeroramp does not penetrate as well as an upstream/downstream impinging jet in a plane aligned with the flow. Next, the Sauter mean droplet diameter distribution was measured downstream of the injector. The droplet diameter was found to vary from 21 to 37 microns and the atomization of the injector does not appear to improve beyond 90 effective jet diameters from the liquid fuel aeroramp. These results were then used to decide on an initial location for the plasma torch. The combined liquid injector/plasma torch system was tested in an unheated (300 K) Mach 2.4 flow with a total pressure of 345 kPa. The liquid fuel (kerosene) volumetric flow rate was varied from 0.66 lpm to 1.22 lpm for the combined liquid injector/plasma torch system. During this testing the plasma torch was operated from 1000 to 5000 watts with 25 slpm of nitrogen and air as feedstocks. The interaction between the spray plume and the plasma torch was observed with direct photographs, videos, and photographs through an OH filter. It is difficult to say that any combustion is present from these photographs. Of course, it would be surprising if much combustion did occur under these cold-flow, low-pressure conditions. Differences between the interaction of the spray plume and the plasma torch with nitrogen and air as feedstocks were documented. According to the OH wavelength filtered photographs the liquid fuel flow rate does appear to have an effect on the height and width of the bright plume. As the liquid fuel flow rate increases the bright plume increases in height by 30% and increases in width slightly (2%). While, a decrease in liquid fuel flow rate resulted in an increase in height by 9% and an increase in width by 10%. Thus, as the liquid fuel flow rate varies the width and height of the bright plume appear to always increase. This can be explained by noticing that the shape of the bright plume changes as the liquid fuel flow rate varies and perhaps anode erosion during testing also plays a part in this variation of the bright plume. From the OH wavelength filtered photographs it was also shown that the bright plume appears to decrease in width by 9% and increase in height by 22% when the plasma torch is set at a lower power setting. When air is used as the torch feedstock, instead of nitrogen, the penetration of the bright plume can increase by as much as 19% in width and 17% in height. It was also found that the height and width of the bright plume decreased slightly (2%) as the fuel flow rate increased when using air as the torch feedstock. Testing in a hot-flow facility is planned. / Master of Science

Research was conducted at Virginia Tech on a high-pressure uncooled plasma torch to study torch operational characteristics with hydrocarbon feedstocks and to determine the feasibility of using the torch as an igniter in scramjet applications. Operational characteristics studied included electrical properties, such as arc stability, voltage-current characteristics and start/re-start capabilities, and mechanical properties, such as coking, electrode erosion and transient to steady-state torch body temperature trends. Possible use of the plasma torch as an igniter in high-speed combustion environments was investigated through the use of emission spectroscopy and a NASA chemical kinetics code. All feedstocks tested; argon, methane, ethylene and propylene, were able to start. The voltage data indicated that there were two preferred operating modes, which were well defined for methane. For all gases, a higher current setting, on the order of 40 A, led to more stable torch operation. A low intensity, high frequency current applied to the torch, along with the primary DC current, resulted in virtual elimination of soot deposits on the anodes. Electrode erosion was found to multiply each time the complexity of the hydrocarbon was increased. Audio and high-speed visual analysis led to identification of 180 Hz plasma formation cycle, related to the three-phase power supply. The spectroscopic analysis aided in the identification of combustion enhancing radicals being produced by the torch, and results of the chemical kinetics analysis verified combustion enhancement and radical production through the use of a basic plasma model. Overall, the results of this study indicate that the plasma torch is a promising source for scramjet ignition, and further study is warranted. / Master of Science

Plasmas térmicos vêm sendo utilizados em um crescente número de aplicações industriais. Na maioria dessas aplicações, as tochas de plasmas (o equipamento utilizado para gerar o plasma) necessitam ser utilizadas por várias centenas de horas antes de qualquer manutenção, a fim de permitir um contínuo processo industrial. Os eletrodos da tocha de plasma, particularmente o catodo, eventualmente irão apresentar sinais de desgaste (erosão), forçando uma substituição dos mesmos e, conseqüentemente, obrigando a uma parada na operação da tocha. Desse modo, a erosão dos eletrodos de uma tocha de plasma (em particular, a erosão do catodo) deve ser minimizada sempre que possível. Este trabalho visa estudar materiais para eletrodos e condições de operação de tochas de plasma a fim de se diminuir a erosão dos eletrodos, particularmente do catodo. Nesse sentido, uma câmara de testes foi construída para simular eletrodos concêntricos de uma tocha de plasma. Um campo magnético externo foi utilizado para movimentar um arco elétrico que foi estabelecido entre os eletrodos concêntricos. Nessa câmara foram estudados diferentes tipos de gases e materiais para o catodo, para tentar aumentar o tempo de vida dos catodos de tocha de plasma. Os resultados obtidos mostraram que: a) A presença de contaminantes nos gases utilizados como gases de plasma alteram as condições da superfície do catodo, diminuindo as taxas de erosão; b) Misturas de gases inertes com gases poliatômicos, quando utilizadas como gases de plasma, contaminam a superfície do catodo, alterando as condições das mesmas, diminuindo as taxas de erosão; c) A presença de contaminantes no material utilizado no catodo, como também a utilização de ligas de cobre como material para os eletrodos, também alteram as características da superfície, aumentando o tempo de vida dos catodos. / Thermal plasmas have shown a growing number of industrial applications. In most of those applications, the plasma torch (the device used to generate the thermal plasma) would need several hundred hours of using before anykind of maintenance, in spite of permit a continuous industrial process. The electrodes of the plasma torch, particularly the cathode, eventually will present signs of erosion, forcing their replacement and, consequently, a stoppage of the torch operation. However, electrode erosion of a plasma torch (cathode erosion in particular) must be minimized as often as possible. The objective of this work is to study materials for plasma torch electrodes and the operation condition of the plasma torch, in order to diminish the erosion of the electrodes (cathode in particular). Therefore, an experimental chamber was built in order to simulate concentric electrodes of a plasma torch. An external magnetic field was used for moving the electric arc that was stablished between the concentric electrodes. Different types of gases and cathode materials have been studied using that chamber. The results obtained so far showed that: a) Contaminants present in the gases used as plasma gases, change the cathode surface conditions, decreasing the erosion rates; b) Mixtures of inert gases with potiatomic gases, when used as plasma gases, contaminate the cathode surface, changing their conditions, decreasing the erosion rates; c) Contaminants in the composition of the materials used in the cathode, and even the use of copper alloys as material for electrodes, changes the surface characteristics, increasing the cathode lifetime.

Plasmas térmicos vêm sendo utilizados em um crescente número de aplicações industriais. Na maioria dessas aplicações, as tochas de plasmas (o equipamento utilizado para gerar o plasma) necessitam ser utilizadas por várias centenas de horas antes de qualquer manutenção, a fim de permitir um contínuo processo industrial. Os eletrodos da tocha de plasma, particularmente o catodo, eventualmente irão apresentar sinais de desgaste (erosão), forçando uma substituição dos mesmos e, conseqüentemente, obrigando a uma parada na operação da tocha. Desse modo, a erosão dos eletrodos de uma tocha de plasma (em particular, a erosão do catodo) deve ser minimizada sempre que possível. Este trabalho visa estudar materiais para eletrodos e condições de operação de tochas de plasma a fim de se diminuir a erosão dos eletrodos, particularmente do catodo. Nesse sentido, uma câmara de testes foi construída para simular eletrodos concêntricos de uma tocha de plasma. Um campo magnético externo foi utilizado para movimentar um arco elétrico que foi estabelecido entre os eletrodos concêntricos. Nessa câmara foram estudados diferentes tipos de gases e materiais para o catodo, para tentar aumentar o tempo de vida dos catodos de tocha de plasma. Os resultados obtidos mostraram que: a) A presença de contaminantes nos gases utilizados como gases de plasma alteram as condições da superfície do catodo, diminuindo as taxas de erosão; b) Misturas de gases inertes com gases poliatômicos, quando utilizadas como gases de plasma, contaminam a superfície do catodo, alterando as condições das mesmas, diminuindo as taxas de erosão; c) A presença de contaminantes no material utilizado no catodo, como também a utilização de ligas de cobre como material para os eletrodos, também alteram as características da superfície, aumentando o tempo de vida dos catodos. / Thermal plasmas have shown a growing number of industrial applications. In most of those applications, the plasma torch (the device used to generate the thermal plasma) would need several hundred hours of using before anykind of maintenance, in spite of permit a continuous industrial process. The electrodes of the plasma torch, particularly the cathode, eventually will present signs of erosion, forcing their replacement and, consequently, a stoppage of the torch operation. However, electrode erosion of a plasma torch (cathode erosion in particular) must be minimized as often as possible. The objective of this work is to study materials for plasma torch electrodes and the operation condition of the plasma torch, in order to diminish the erosion of the electrodes (cathode in particular). Therefore, an experimental chamber was built in order to simulate concentric electrodes of a plasma torch. An external magnetic field was used for moving the electric arc that was stablished between the concentric electrodes. Different types of gases and cathode materials have been studied using that chamber. The results obtained so far showed that: a) Contaminants present in the gases used as plasma gases, change the cathode surface conditions, decreasing the erosion rates; b) Mixtures of inert gases with potiatomic gases, when used as plasma gases, contaminate the cathode surface, changing their conditions, decreasing the erosion rates; c) Contaminants in the composition of the materials used in the cathode, and even the use of copper alloys as material for electrodes, changes the surface characteristics, increasing the cathode lifetime.

Orientador: Edison Bittencourt / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-26T21:57:48Z (GMT). No. of bitstreams: 1 Silva_SoniaFonsecaCostae_D.pdf: 7122538 bytes, checksum: 168b9088ec0fd3c2e7dc5392747cded0 (MD5) Previous issue date: 2015 / Resumo: Compósitos ablativos são vastamente utilizados em divergentes de motores usados em veículos espaciais, em particular nos veículos em desenvolvimento no Instituto de Aeronáutica e Espaço, como por exemplo, o Veículo Lançador de Satélite. Tais divergentes podem ser produzidos por diversos processos, entre eles a bobinagem. Atualmente é empregado o processo de bobinagem paralela para a fabricação desses elementos. Porém, visando obter-se um melhor desempenho ablativo e otimização da massa para os divergentes, propõe-se uma inovação no processo de fabricação para estruturas ablativas, a bobinagem inclinada em fitas tecidas. Neste trabalho foi realizado um estudo teórico experimental da ablação em compósitos bobinados obtidos através dos dois processos de bobinagem, paralela e inclinada. Uma tocha de plasma é usada para simular as condições de operação do material em um divergente. O material utilizado como reforço do compósito foi um tecido de fibra de carbono e o polímero utilizado como matriz foi uma resina fenólica tipo resol. Nestas condições, foram avaliadas a taxa de perda de massa e as temperaturas atingidas na face exposta a tocha, tendo como parâmetro o fluxo térmico do jato de plasma. Os dados experimentais foram comparados com os resultados numéricos de uma simulação computacional. Embora não tenha sido obtida uma perfeita concordância entre os resultados numéricos e experimentais, a ordem de magnitude e o comportamento de variação dos parâmetros avaliados podem ser considerados fisicamente coerentes e dentro dos limites do modelo teórico proposto. Os resultados obtidos permitem estimar a taxa de perda de massa de acordo com o fluxo térmico e indicam um melhor desempenho ablativo das amostras obtidas por bobinagem inclinada em comparação com as amostras obtidas por bobinagem paralela / Abstract: Ablative composites are widely used in nozzles of propeller engines used in space vehicles, as the Satellite Launching Vehicle in development at Aeronautics and Space Institute, for example. Such nozzle extension can be produced by various processes, including wrapping tape. Currently is employed the parallel wrapping process to manufacture these elements. However, in order to get a better ablative performance and mass optimization for the nozzle extensions, it has been proposed an innovation in the manufacturing process for ablative structures, biased tape wrapping. In this paper is presented a theoretical study of experimental ablation in wound composite obtained by the two wrapping processes, parallel and biased tape. A plasma torch has used to simulate the operating conditions of the material in the nozzle extension. The composite has used as reinforcement a carbon fiber fabric with a resol phenolic resin matrix. Thus, it has evaluated the weight loss rate and the temperatures reached on the face to the side exposed to the torch, with the heat flux parameter of the plasma jet. The experimental data were compared with the numerical results of a computer simulation. Although not obtained a perfect agreement between the numerical and experimental results, the order of magnitude and the pattern of variation of the evaluated parameters can be considered physically consistent and within the limits of the proposed theoretical model. The results obtained allow us to estimate the mass loss rate in accordance with the thermal flow and indicate a better ablative performance of samples obtained by biased tape wrapping in comparison with the samples obtained by parallel wrapping / Doutorado / Ciencia e Tecnologia de Materiais / Doutora em Engenharia Quimica

An integrated aerodynamic-ramp-injector/plasma-torch-igniter of original design was tested in a Mâ = 2, unvitiated, heated flow facility arranged as a diverging duct scramjet combustor. The facility operated at a total temperature of 1000 K and total pressure of 330 kPa. Hydrogen (H2), ethylene (C2H4) and methane (CH4) were used as fuels, and a wide range of global equivalence ratios were tested. The main data obtained were wall static pressure measurements, and the presence of combustion was determined based on the pressure rises obtained. Supersonic and dual-mode combustion were achieved with hydrogen and ethylene fuel, whereas very limited heat release was obtained with the methane. Global operability limits were determined to be 0.07 < Ï < 0.31 for hydrogen, and 0.14 < Ï < 0.48 for ethylene. The hydrogen fuel data for the aeroramp/torch system was compared to data from a physical 10 unswept compression ramp injector and similar performance was found with the two arrangements. With hydrogen and ethylene as fuels and the aeroramp/plasma-torch system, the effect of varying the air total temperature was investigated. Supersonic combustion was achieved with temperatures as low as 530K and 680K for the two fuels, respectively. These temperatures are facility/operational limits, not combustion limits. The pressure profiles were analyzed using the Ramjet Propulsion Analysis (RJPA) code. Results indicate that both supersonic and dual-mode ramjet combustion were achieved. Combustion efficiencies varied with Ï from a high of about 75% to a low of about 45% at the highest Ï . With a theoretical diffuser and nozzle assumed for the configuration and engine, thrust was computed for each fuel. Fuel specific impulse was on average 3000 and 1000 seconds for hydrogen and ethylene respectively, and air specific impulse varied from a low of about 9 sec to a high of about 24 sec (for both fuels) for the To = 1000K test condition. The GASP RANS code was used to numerically simulate the injection and mixing process of the fuels. The results of this study were very useful in determining the suitability of the selected plasma torch locations. Further, this tool can be used to determine whether combustion is theoretically possible or not. / Ph. D.

O principal objetivo deste trabalho foi apresentar o projeto, o desenvolvimento, a caracterização e a aplicação de um novo dispositivo híbrido gerador de plasma. Este dispositivo consiste em uma tocha de plasma híbrida, a qual é caracterizada pela formação simultânea de dois arcos plasmas, em apenas um dispositivo, que geram um jato de plasma com elevada densidade de energia. Esta tocha é proveniente da união de dois processos geradores de plasma: Plasma Não-Transferido e Propulsor Magnetoplasmadinâmico. A tocha de plasma híbrida desenvolvida no Laboratório de Soldagem & Técnicas Conexas foi submetida aos seguintes testes: testes iniciais de funcionamento para verificar possíveis problemas de projeto e limites de operação da tocha; testes experimentais para caracterização da tocha de plasma híbrida, os quais consistiram em determinar as curvas características de tensão e corrente, o comprimento do jato de plasma, a distribuição de temperatura do jato de plasma expulso para fora da câmara, e a força propulsora resultante do jato de plasma; e testes de aplicação da tocha de plasma híbrida em processos de fabricação, tais como soldagem, corte e endurecimento superficial. Com base nos resultados obtidos para os testes de funcionamento do dispositivo, alguns problemas de isolamento elétrico e térmico foram encontrados e resolvidos. Quanto aos resultados dos testes de caracterização, os parâmetros de funcionamento da tocha de plasma híbrida apresentaram influência significativa sobre as curvas características de tensão e corrente, os comprimentos do jato de plasma, as forças propulsoras resultantes e as distribuições de temperatura. Os resultados obtidos nos testes de aplicação do dispositivo em processos de fabricação foram satisfatórios, isto é, foi possível realizar soldagens, cortes e endurecimento superficial com a tocha de plasma híbrida. Contudo, um novo dispositivo gerador de plasma foi desenvolvido para aplicações em processos de fabricação, porém novos estudos devem ser realizados para encontrar melhores parâmetros e assim conseguir soldagem, corte e endurecimento superficial com excelentes qualidades. / The main objective of this work was to present the project, development, characterization and application to a new hybrid plasma generator device. This device consists of a hybrid plasma torch that is characterized by the simultaneous formation of two plasma arcs in only one device, generating a plasma jet with high energy density. This torch arises from the union of two different plasma processes: Plasma Non-transferred and Magnetoplasmadynamic Thruster. The hybrid plasma torch developed in the Welding & Related Techniques Laboratory was submitted to the following trials: trials of operation to identify possible design problems and operations torch limits; trials to characterization of hybrid plasma torch that determined the characteristics curves of voltage and current, the length, the temperature distribution, and the thruster of the plasma jet; and application trials of hybrid plasma torch in manufacturing process, such as welding, cutting and hardening surface. Based at initial operation trials results with the device, some electrical and thermal insulation problems were found and solved. Concerning the results of the characterization trials, the hybrid plasma torch parameters had a significant influence over the voltage and current curves, the lengths of the plasma jet, the resultant thrusters and the temperature distributions. The results obtained in manufacturing process application trials were satisfactory, i.e. was possible to carry out welding, cutting and hardening surface with the hybrid plasma torch. However, a new plasma generated device was developed for application in manufacturing processes, but further studies should be performed to find the best parameters to acquire excellent qualities of welding, cutting and hardening surface.

O principal objetivo deste trabalho foi apresentar o projeto, o desenvolvimento, a caracterização e a aplicação de um novo dispositivo híbrido gerador de plasma. Este dispositivo consiste em uma tocha de plasma híbrida, a qual é caracterizada pela formação simultânea de dois arcos plasmas, em apenas um dispositivo, que geram um jato de plasma com elevada densidade de energia. Esta tocha é proveniente da união de dois processos geradores de plasma: Plasma Não-Transferido e Propulsor Magnetoplasmadinâmico. A tocha de plasma híbrida desenvolvida no Laboratório de Soldagem & Técnicas Conexas foi submetida aos seguintes testes: testes iniciais de funcionamento para verificar possíveis problemas de projeto e limites de operação da tocha; testes experimentais para caracterização da tocha de plasma híbrida, os quais consistiram em determinar as curvas características de tensão e corrente, o comprimento do jato de plasma, a distribuição de temperatura do jato de plasma expulso para fora da câmara, e a força propulsora resultante do jato de plasma; e testes de aplicação da tocha de plasma híbrida em processos de fabricação, tais como soldagem, corte e endurecimento superficial. Com base nos resultados obtidos para os testes de funcionamento do dispositivo, alguns problemas de isolamento elétrico e térmico foram encontrados e resolvidos. Quanto aos resultados dos testes de caracterização, os parâmetros de funcionamento da tocha de plasma híbrida apresentaram influência significativa sobre as curvas características de tensão e corrente, os comprimentos do jato de plasma, as forças propulsoras resultantes e as distribuições de temperatura. Os resultados obtidos nos testes de aplicação do dispositivo em processos de fabricação foram satisfatórios, isto é, foi possível realizar soldagens, cortes e endurecimento superficial com a tocha de plasma híbrida. Contudo, um novo dispositivo gerador de plasma foi desenvolvido para aplicações em processos de fabricação, porém novos estudos devem ser realizados para encontrar melhores parâmetros e assim conseguir soldagem, corte e endurecimento superficial com excelentes qualidades. / The main objective of this work was to present the project, development, characterization and application to a new hybrid plasma generator device. This device consists of a hybrid plasma torch that is characterized by the simultaneous formation of two plasma arcs in only one device, generating a plasma jet with high energy density. This torch arises from the union of two different plasma processes: Plasma Non-transferred and Magnetoplasmadynamic Thruster. The hybrid plasma torch developed in the Welding & Related Techniques Laboratory was submitted to the following trials: trials of operation to identify possible design problems and operations torch limits; trials to characterization of hybrid plasma torch that determined the characteristics curves of voltage and current, the length, the temperature distribution, and the thruster of the plasma jet; and application trials of hybrid plasma torch in manufacturing process, such as welding, cutting and hardening surface. Based at initial operation trials results with the device, some electrical and thermal insulation problems were found and solved. Concerning the results of the characterization trials, the hybrid plasma torch parameters had a significant influence over the voltage and current curves, the lengths of the plasma jet, the resultant thrusters and the temperature distributions. The results obtained in manufacturing process application trials were satisfactory, i.e. was possible to carry out welding, cutting and hardening surface with the hybrid plasma torch. However, a new plasma generated device was developed for application in manufacturing processes, but further studies should be performed to find the best parameters to acquire excellent qualities of welding, cutting and hardening surface.