Experimental and theoretical investigations of mechanisms responsible for plasma jets formation at PALS

AbstractRecent experimental results demonstrated that well formed plasma jets can be produced at laser interaction with targets made of materials with high atomic number (A ≥ 29 where A = 29 corresponds to Cu). On the contrary, it is impossible to launch a plasma jet on low-A material targets like plastic. This paper is aimed at explanation of this difference by considering mechanisms responsible for plasma jet formation, i.e., the radiative cooling of ablative plasma and the influence of target irradiation annular profile speculated hitherto, newly complemented by different expansion regimes of the Cu and plastic plasmas (provided by numerical simulations). The experiment was carried out with the PALS iodine laser. Two different planar massive targets, plastic and Cu, as well as the plastic target covered by thin Cu layers of various thicknesses were irradiated by the third harmonic laser beam of energy of 30 J, pulse duration of 250 ps (full width at half maximum), and the focal spot radius of 400 µm. To find the most suitable range of these layers (from 28 to 190 nm) a simple analytical model of laser-driven evaporation was developed. Three-frame laser interferometer and an X-ray streak camera were used as two main diagnostic tools. Numerical modeling was performed with the use of two-dimensional hydrodynamic code ATLANT-HE. Results provided from experiments and theoretical analyses have proved that the process of plasma jet formation is rather complex. Relative importance of the three mechanisms mentioned above depends on the target irradiation geometry as well as the target material used.

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Interaction of two plasma jets produced successively from Cu target

Laser and Particle Beams ◽

10.1017/s0263034610000492 ◽

2010 ◽

Vol 28 (3) ◽

pp. 497-504 ◽

Cited By ~ 3

Author(s):

A. Kasperczuk ◽

T. Pisarczyk ◽

J. Badziak ◽

S. Borodziuk ◽

T. Chodukowski ◽

...

Keyword(s):

Laser Beam ◽

Target Surface ◽

Plasma Jet ◽

Plasma Jets ◽

Diagnostic Tools ◽

Jet Formation ◽

Simple Method ◽

Third Harmonic ◽

Laser Facility ◽

Focal Spot Diameter

AbstractOur earlier papers demonstrate a very simple method of plasma jet formation, consisting in irradiating a massive planar target of a relatively high atomic number by a partly defocused laser beam. Our present interest is concentrated on interaction of the plasma jet with other media. This paper is aimed at investigations of interaction of two jets launched successively on Cu target. Our attention was paid to the role of radiative cooling in the plasma jet formation. The experiment was carried out at the PALS iodine laser facility. The laser provided a 250-ps (full width at half maximum) pulse with energy of 130 J at the third harmonic frequency (λ3 = 0.438 µm). Two successive jets were produced on a massive flat Cu target provided with a cylindrical channel 5 mm long and 400 µm in diameter. Since the focal spot diameter of the laser beam on the target surface was larger than that of the channel (800 µm), the annular irradiation of the target face resulted in creation of the first plasma jet, whereas the second jet was produced by action of the central part of laser beam on the channel wall. Three-frame interferometric system, X-ray streak camera, and a set of ion collectors were used as diagnostic tools.

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Interferometric investigations of influence of target irradiation on the parameters of laser-produced plasma jets

Laser and Particle Beams ◽

10.1017/s0263034607000547 ◽

2007 ◽

Vol 25 (3) ◽

pp. 425-433 ◽

Cited By ~ 13

Author(s):

A. Kasperczuk ◽

T. Pisarczyk ◽

S. Borodziuk ◽

J. Ullschmied ◽

E. Krousky ◽

...

Keyword(s):

Focal Spot ◽

Laser Energy ◽

Plasma Jet ◽

Plasma Jets ◽

Plasma Expansion ◽

Third Harmonic ◽

Fundamental Process ◽

Laser Produced Plasma ◽

Laser Facility ◽

Planar Target

Our recent experimental results demonstrate that the formation of plasma jets is a fundamental process accompanying the laser produced plasma expansion, if a massive planar target with relatively high atomic number is irradiated by a defocused laser beam. In this paper some new results on the influence of target irradiation conditions on plasma jet parameters are presented. The experiment was carried out at the PALS iodine laser facility, with the third harmonic beam of the pulse duration of 250 ps (FWHM). The beam energies varied in the range of 13–160 J, the focal spot radii in the range of 35–600 µm. The planar massive targets used in the experiment were made of Cu, Ag and Ta. For measurements of the electron density evolution a three frame interferometric system was employed. The jets were observed in the whole range of the laser energy used. The initial velocities of the plasma jets produced in the reported experiment reached the value of up to 7·107 cm/s, the jets were up to 4 mm long including the jet pedestal and about 400 µm in diameter. Calculations of the efficiency of the plasma jet production show that it decreases with increasing the laser energy.

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High-Speed Video Analysis of the Process Stability in Plasma Spraying

Journal of Thermal Spray Technology ◽

10.1007/s11666-021-01159-1 ◽

2021 ◽

Author(s):

K. Bobzin ◽

M. Öte ◽

M. A. Knoch ◽

I. Alkhasli ◽

H. Heinemann

Keyword(s):

Plasma Spraying ◽

High Speed ◽

Plasma Jet ◽

Plasma Jets ◽

Time Dependent ◽

Acquisition Time ◽

Fast Fourier Transformation ◽

Frequency Spectra ◽

Dependent Signal ◽

The Stability

AbstractIn plasma spraying, instabilities and fluctuations of the plasma jet have a significant influence on the particle in-flight temperatures and velocities, thus affecting the coating properties. This work introduces a new method to analyze the stability of plasma jets using high-speed videography. An approach is presented, which digitally examines the images to determine the size of the plasma jet core. By correlating this jet size with the acquisition time, a time-dependent signal of the plasma jet size is generated. In order to evaluate the stability of the plasma jet, this signal is analyzed by calculating its coefficient of variation cv. The method is validated by measuring the known difference in stability between a single-cathode and a cascaded multi-cathode plasma generator. For this purpose, a design of experiment, covering a variety of parameters, is conducted. To identify the cause of the plasma jet fluctuations, the frequency spectra are obtained and subsequently interpreted by means of the fast Fourier transformation. To quantify the significance of the fluctuations on the particle in-flight properties, a new single numerical parameter is introduced. This parameter is based on the fraction of the time-dependent signal of the plasma jet in the relevant frequency range.

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Tiny Cold Atmospheric Plasma Jet for Biomedical Applications

Processes ◽

10.3390/pr9020249 ◽

2021 ◽

Vol 9 (2) ◽

pp. 249

Author(s):

Zhitong Chen ◽

Richard Obenchain ◽

Richard E. Wirz

Keyword(s):

Biomedical Applications ◽

Plasma Jet ◽

Discharge Voltage ◽

Plasma Jets ◽

Atmospheric Plasma ◽

Physical Parameters ◽

Cold Atmospheric Plasma ◽

Water Metal ◽

Plasma Probe ◽

Jet Nozzle

Conventional plasma jets for biomedical applications tend to have several drawbacks, such as high voltages, high gas delivery, large plasma probe volume, and the formation of discharge within the organ. Therefore, it is challenging to employ these jets inside a living organism’s body. Thus, we developed a single-electrode tiny plasma jet and evaluated its use for clinical biomedical applications. We investigated the effect of voltage input and flow rate on the jet length and studied the physical parameters of the plasma jet, including discharge voltage, average gas and subject temperature, and optical emissions via spectroscopy (OES). The interactions between the tiny plasma jet and five subjects (de-ionized (DI) water, metal, cardboard, pork belly, and pork muscle) were studied at distances of 10 mm and 15 mm from the jet nozzle. The results showed that the tiny plasma jet caused no damage or burning of tissues, and the ROS/RNS (reactive oxygen/nitrogen species) intensity increased when the distance was lowered from 15 mm to 10 mm. These initial observations establish the tiny plasma jet device as a potentially useful tool in clinical biomedical applications.

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Electron dynamics and plasma jet formation in a helium atmospheric pressure dielectric barrier discharge jet

Applied Physics Letters ◽

10.1063/1.3628455 ◽

2011 ◽

Vol 99 (12) ◽

pp. 121501 ◽

Cited By ~ 49

Author(s):

Q. Th. Algwari ◽

D. O'Connell

Keyword(s):

Dielectric Barrier Discharge ◽

Atmospheric Pressure ◽

Barrier Discharge ◽

Plasma Jet ◽

Electron Dynamics ◽

Jet Formation ◽

Dielectric Barrier

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Tailoring the Chemistry of Plasma-Activated Water Using a DC-Pulse-Driven Non-Thermal Atmospheric-Pressure Helium Plasma Jet

Plasma ◽

10.3390/plasma2020010 ◽

2019 ◽

Vol 2 (2) ◽

pp. 127-137 ◽

Cited By ~ 1

Author(s):

Oh ◽

Szili ◽

Hatta ◽

Ito ◽

Shirafuji

Keyword(s):

Hydrogen Peroxide ◽

Atmospheric Pressure ◽

Pulse Width ◽

Plasma Jet ◽

Plasma Jets ◽

Helium Plasma ◽

Uv Absorption Spectroscopy ◽

Pulse Polarity ◽

Plasma Activated Water

We investigate the use of a DC-pulse-driven non-thermal atmospheric-pressure He plasma jet in the regulation of hydrogen peroxide (H2O2), nitrite (NO2−), nitrate (NO3−), and oxygen (O2) in deionized (DI) water. The production of these molecules is measured by in situ UV absorption spectroscopy of the plasma-activated water (PAW). Variations in the pulse polarity and pulse width have a significant influence on the resultant PAW chemistry. However, the trends in the concentrations of H2O2, NO2−, NO3−, and O2 are variable, pointing to the possibility that changes in the pulse polarity and pulse width might influence other plasma variables that also impact on the PAW chemistry. Overall, the results presented in this study highlight the possibility of using DC-pulse-driven plasma jets to tailor the chemistry of PAW, which opens new opportunities for the future development of optimal PAW formulations across diverse applications ranging from agriculture to medicine.

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Applications of the COST Plasma Jet: More than a Reference Standard

Plasma ◽

10.3390/plasma2030023 ◽

2019 ◽

Vol 2 (3) ◽

pp. 316-327 ◽

Cited By ~ 9

Author(s):

Gorbanev ◽

Golda ◽

Gathen ◽

Bogaerts

Keyword(s):

Chemical Properties ◽

Plasma Jet ◽

Plasma Jets ◽

Physical And Chemical Properties ◽

Reference Standard ◽

Liquid Systems ◽

Plasma Research ◽

The Cost ◽

Physical And Chemical ◽

And Chemical Properties

The rapid advances in the field of cold plasma research led to the development of many plasma jets for various purposes. The COST plasma jet was created to set a comparison standard between different groups in Europe and the world. Its physical and chemical properties are well studied, and diagnostics procedures are developed and benchmarked using this jet. In recent years, it has been used for various research purposes. Here, we present a brief overview of the reported applications of the COST plasma jet. Additionally, we discuss the chemistry of the plasma-liquid systems with this plasma jet, and the properties that make it an indispensable system for plasma research.

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