Generation of Long Laminar Plasma Jets: Experimental and Numerical Analyses

  • Sen-Hui Liu
  • Shan-Lin Zhang
  • Cheng-Xin Li
  • Lu Li
  • Jia-Hua Huang
  • Juan Pablo Trelles
  • Anthony B. Murphy
  • Chang-Jiu Li
Original Paper


A novel direct current non-transferred arc plasma torch that can generate silent, stable and super-long laminar plasma jets in atmospheric air is investigated. The results showed that laminar plasma jets of length ranging from 100 to 720 mm in length can be generated by controlling the gas input rate ranging from 8.5 to 15 L min−1 and the output power from 8.5 to 28 kW. The length of the plasma jets generally increased with the output power and gas flow rate. Observations of temporal evolution of the plasma jet appearance and the voltage demonstrated that the jet is highly stable in the atmospheric environment. The fluid dynamic properties of the laminar plasma jet were studied using a numerical simulation incorporating a laminar flow model and an RNG turbulent flow model. Simulation results show the expansion of a high temperature region close to the torch nozzle exit, corresponding to a bright region observed in experiments.


Laminar plasma jet Voltage current characteristics Voltage vibration Numerical simulation 

List of Symbols


Specific heat at constant pressure (J kg−1K−1)


Electric field (V m−1)


Temperature (K)


Power (W)


Current (A)


Gas flow rate (kg s−1)


Turbulent kinetic energy (m2 s−2)

Greek Symbols


Dissipation rate of turbulent kinetic energy (m2 s−3)


Net emission coefficient (W m−3sr−1)


Thermal conductivity (W m−1K−1)


Dynamic viscosity (kg m−1s−1)


Turbulent viscosity (kg m−1s−1)


Effective viscosity (kg m−1s−1)


Electrical conductivity (S m−1)


Density (kg m−3)


Electric potential (V)



Local thermodynamic equilibrium


Renormalization group methods


Magnetohydrodynamic model


Net emission coefficient



The authors are grateful to Prof. Ren-zhong Huang from the Department of New Materials of Guangzhou Non-Ferrous Metal Research Institute for his selfless help with the computer programming. This work was supported by the Natural Key R&D Program of China (Basic Research Project, Grant No. 2017YFB0306104), the Ph.D. Short-term Academic Visiting Program of Graduate School of Xi’an Jiaotong University and National Ph.D. Degree Program of the China Scholarship Council.

Supplementary material

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Supplementary material 1 (GIF 6103 kb)
11090_2018_9949_MOESM2_ESM.tif (4.2 mb)
Supplementary material 2 (TIFF 4324 kb)


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Sen-Hui Liu
    • 1
    • 3
  • Shan-Lin Zhang
    • 1
  • Cheng-Xin Li
    • 1
  • Lu Li
    • 2
  • Jia-Hua Huang
    • 2
  • Juan Pablo Trelles
    • 3
  • Anthony B. Murphy
    • 4
  • Chang-Jiu Li
    • 1
  1. 1.State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’anChina
  2. 2.Zhenhuo Plasma Technology Co., LtdChenduChina
  3. 3.Department of Mechanical EngineeringUniversity of Massachusetts LowellLowellUSA
  4. 4.CSIRO ManufacturingLindfieldAustralia

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