Schlieren flow visualization of helium atmospheric plasma jet and influence of the gas flow rate and applied voltage frequency

In this paper, a construction microwave induced plasma jet(MIPJ) system was used to produce a non-thermal plasma jet at atmospheric pressure, at standard frequency of 2.45 GHz and microwave power of 800 W. The working gas Argon (Ar) was supplied to flow through the torch with adjustable flow rate using flow meter regulator. The influence of the MIPJ parameters such as applied voltage and argon gas flow rate on macroscopic microwave plasma parameters were studied. The macroscopic parameters results show increasing of microwave plasma jet length with increasing of applied voltage, argon gas flow rate where the plasma jet length exceed 12 cm as maximum value. While the increasing of argon gas flow rate will cause increasing into the argon gas temperature, where argon gas temperature the exceed 350 ? as maximum value and study the effect of gas flow rate on the optical properties

Download Full-text

Evaluation of Solid Lubricant Coatings for Low Friction and Wear Resistance Using the Atmospheric Plasma Spray

Materials Science Forum ◽

10.4028/www.scientific.net/msf.449-452.777 ◽

2004 ◽

Vol 449-452 ◽

pp. 777-780 ◽

Cited By ~ 4

Author(s):

Chang Min Han ◽

Han Shin Choi ◽

Chang Hee Lee ◽

Hyung Jun Kim ◽

S.Y. Hwang

Keyword(s):

Flow Rate ◽

Friction And Wear ◽

Gas Flow ◽

Plasma Jet ◽

Hydrogen Gas ◽

Atmospheric Plasma ◽

Dry Sliding Wear ◽

Coating Properties ◽

Gas Flow Rate ◽

Jet Characteristics

A blended NiCr-Cr2O3-Ag-BaF2/CaF2 feedstock was sprayed using an atmospheric plasma spraying process. Due to the differences in physical and thermophysical properties of each constituent, coating microstructures and resulting coating properties were largely dependent on the interactions between each constituent phase and plasma jet in view of the physics of thermal spraying. Thus, hydrogen gas flow rate was changed to affect the plasma jet characteristics such as gas enthalpy and gas thermal conductivity in this study. According to it, evolutions of chemical composition and microstructures of the as-sprayed coatings were observed. As the hydrogen gas flow rate was increased, Cr2O3 weight fraction was increased with the decrease of Ag and porosity. Vickers microhardness and bond strength of the coatings showed consistent behaviors to the phase composition and microstructures. Friction coefficient and weight loss during a pin-on-disc dry sliding wear test were measured from room temperature to 500°C at the interval of 100°C. Finally, the effects of phase fraction and coating properties on the friction and wear were investigated.

Download Full-text

Electrical and Spectroscopic Diagnostics of Atmospheric Pressure DBD Plasma Jet

Journal of Bangladesh Academy of Sciences ◽

10.3329/jbas.v40i1.28322 ◽

2016 ◽

Vol 40 (1) ◽

pp. 23-36

Author(s):

NC Roy ◽

MR Talukder

Keyword(s):

Flow Rate ◽

Applied Voltage ◽

Atmospheric Pressure ◽

Gas Flow ◽

Optical Emission ◽

Plasma Jet ◽

Diagnostic Techniques ◽

Gas Temperature ◽

Gas Flow Rate ◽

Dbd Plasma

Atmospheric pressure capillary dielectric barrier oxygen discharge plasma jet is developed to generate nonthermal plasma using unipolar positive pulse power supply. Both electrical and optical diagnostic techniques were used to characterize the produced plasma as functions of applied voltage and gas flow rate. Electrical diagnostics indicated that the discharge frequency decreased with gas flow rate but increased with the applied voltage. Analytical results obtained from the optical emission spectroscopic data revealed the gas temperature, excitation temperature and electron density. Gas temperature was found to decrease with increasing oxygen flow rate but increase linearly with applied voltage. The produced plasma was applied preliminarily to study the inactivation yield of Fusarium oxysporum fungus infected potato samples.Journal of Bangladesh Academy of Sciences, Vol. 40, No. 1, 23-36, 2016

Download Full-text

Parameters Affecting the Antimicrobial Properties of Cold Atmospheric Plasma Jet

Journal of Clinical Medicine ◽

10.3390/jcm8111930 ◽

2019 ◽

Vol 8 (11) ◽

pp. 1930 ◽

Cited By ~ 7

Author(s):

Bih-Show Lou ◽

Chih-Ho Lai ◽

Teng-Ping Chu ◽

Jang-Hsing Hsieh ◽

Chun-Ming Chen ◽

...

Keyword(s):

Gas Flow ◽

Treatment Time ◽

Plasma Jet ◽

Atmospheric Plasma ◽

Gas Flow Rate ◽

Cold Atmospheric Plasma ◽

E Coli ◽

Antimicrobial Efficiency ◽

Ar Gas ◽

Sample Distance

Using the Taguchi method to narrow experimental parameters, the antimicrobial efficiency of a cold atmospheric plasma jet (CAPJ) treatment was investigated. An L9 array with four parameters of CAPJ treatments, including the application voltage, CAPJ-sample distance, argon (Ar) gas flow rate, and CAPJ treatment time, were applied to examine the antimicrobial activity against Escherichia coli (E. coli). CAPJ treatment time was found to be the most influential parameter in its antimicrobial ability by evaluation of signal to noise ratios and analysis of variance. 100% bactericidal activity was achieved under the optimal bactericidal activity parameters including the application voltage of 8.5 kV, CAPJ-sample distance of 10 mm, Ar gas flow rate of 500 sccm, and CAPJ treatment time of 300 s, which confirms the efficacy of the Taguchi method in this design. In terms of the mechanism of CAPJ’s antimicrobial ability, the intensity of hydroxyl radical produced by CAPJ positively correlated to its antimicrobial efficiency. The CAPJ antimicrobial efficiency was further evaluated by both DNA double-strand breaks analysis and scanning electron microscopy examination of CAPJ treated bacteria. CAPJ destroyed the cell wall of E. coli and further damaged its DNA structure, thus leading to successful killing of bacteria. This study suggests that optimal conditions of CPAJ can provide effective antimicrobial activity and may be grounds for a novel approach for eradicating bacterial infections.

Download Full-text

Effects of Gas Flow Rate on the Discharge Characteristics of a DC Excited Plasma Jet

Plasma Science and Technology ◽

10.1088/1009-0630/17/9/04 ◽

2015 ◽

Vol 17 (9) ◽

pp. 738-742 ◽

Cited By ~ 4

Author(s):

Xuechen Li ◽

Pengying Jia ◽

Cong Di ◽

Wenting Bao ◽

Chunyan Zhang

Keyword(s):

Flow Rate ◽

Gas Flow ◽

Plasma Jet ◽

Gas Flow Rate ◽

Discharge Characteristics

Download Full-text

The Effect of Mass Transfer Rate-Time in Bubbles on Removal of Azoxystrobin in Water by Micro-Sized Jet Array Discharge

Catalysts ◽

10.3390/catal11101169 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1169

Author(s):

Feng Chen ◽

Dezheng Yang ◽

Feng Yu ◽

Yang Kun ◽

Ying Song

Keyword(s):

Mass Transfer ◽

Removal Efficiency ◽

Flow Rate ◽

Applied Voltage ◽

Transfer Rate ◽

Gas Flow ◽

Mass Transfer Rate ◽

Initial Solution ◽

Solution Temperature ◽

Gas Flow Rate

In this work, the azoxystrobin removal in water by using a micro-size discharge array was investigated, and the removal efficiency can reach as high as 98.1% after 9 min plasma treatment as well as the energy utilization being only 0.73 g/(kW·h). Based on the relationship between the generation of gas bubbles and parameters of gas-liquid discharge, it was found that the variation of applied voltage, gas flow rate and initial solution temperature could cause particle number change, mass transfer rate change and the mass transfer time change, which significantly affected the practical applications at last. The experimental results indicated that when gas flow rate was 0.7 SLM (Standard Liter per Minute) and the initial solution temperature was 297 K with the applied voltage of 8 kV and discharge frequency of 6 kHz, the removal efficiency of azoxystrobin achieved maximum. Based on the analysis results of liquid mass spectrometry, the removal pathways of azoxystrobin were supposed by the decomposed by-products. Toxicity tests indicated that the decomposed products were safe and non-toxic. So, this study may reveal an azoxystrobin degradation mechanism and provide a safe, reliable and effective way for azoxystrobin degradation.

Download Full-text

OPTIMIZATION OF NON THERMAL PLASMA REACTOR PERFORMANCE FOR THE DECOMPOSITION OF XYLENE

Jurnal Teknologi ◽

10.11113/jt.v78.7595 ◽

2016 ◽

Vol 78 (8) ◽

Author(s):

Nor Faraliana Shazwani Nor Azmi ◽

Abdullahi Mohammed Evuti ◽

Mohd Ariffin Abu Hassan ◽

R. K. Raja Ibrahim

Keyword(s):

Flow Rate ◽

Thermal Plasma ◽

Applied Voltage ◽

Gas Flow ◽

Plasma Reactor ◽

Gas Flow Rate ◽

Reactor Performance ◽

Model Predictions ◽

Non Thermal Plasma ◽

Discharge Gap

Non Thermal Plasma (NTP) is an emerging method used for the decomposition of volatile organic compounds (VOCs). This research focuses on the optimization of NTP reactor performance for decomposition of xylene from wastewater using response surface methodology (RSM) by operating the NTP reactor at applied voltage of 12-15 kV, discharge gap of 2.0-3.0 cm and gas flow rate of 2.0-5.0 L/min. An optimum xylene removal efficiency of 81.98% was obtained at applied voltage 15kV, discharge gap 2.09cm and gas flow rate at 2.36 L/min. The experimental removal efficiencies and model predictions were in close agreement with an error of 0.63%.

Download Full-text