Laser-induced plasma temperature

Zhang, Shudi; Wang, Xiaohua; He, Miaohong; Jiang, Yunbin; Zhang, Bochao; Hang, Wei; Huang, Benli

doi:10.1016/j.sab.2014.04.009

Cited by 149 publications

(62 citation statements)

References 220 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This depends on the plasma parameters such as the ambient gas, laser energy and pulse duration used in the experiments [27,28]. The most commonly used method to warrant the existence of LTE is the electron energy distribution function (EEDF) Maxwell distribution, and the McWhirter criterion [23,[29][30][31]. The McWhirter criterion defines the minimum electron number density which must be present in order for LTE to exist, which can be expressed mathematically as [3]:…”

Section: The Local Thermodynamic Equilibrium and The Optical Thinnessmentioning

confidence: 99%

“…Assuming plasma in LTE, the population of the energy levels of the species obeys the Boltzmann's distribution law [17,23], which can be given by the expression: For experimental systems, we can replace the emissivity by the line intensity, and by taking the natural logarithm of Eq. (4), we obtain the expression in the form:…”

Section: Theoretical Model Of the Electron Temperaturementioning

confidence: 99%

See 1 more Smart Citation

Influence of laser energy on the electron temperature of a laser-induced Mg plasma

Asamoah

Yao

2016

Appl. Phys. B

View full text Add to dashboard Cite

radiations in this process are used for the identification of the elemental composition of the sample [7][8][9].LIBS offers many advantages over other spectroscopic techniques such as mass spectroscopy, electrode spark and inductively coupled plasma. Some of LIBS unique advantages include the ability to make in situ analysis even in hostile environment, remote sensing, little or no preparation of the sample, and multi-element analysis [10][11][12]. Based on these advantages, LIBS has been extensively investigated on several samples including liquids [13], gases [14] and as well from non-conducting and conducting solids [15].LIBS is also a spectroscopic technique for the determination of the density of electron, electron temperature and number densities of the plasma plume [16,17]. Laserinduced plasma temperatures are influenced by various experimental conditions such as ambient surrounding, laser energy and laser pulse width. Most of the studies on LIBS temperatures report that the plasma temperature tends to increase with increasing laser energy, pulse width, laser wavelength and ambient pressure [18][19][20][21].Although LIBS has been employed successfully in several experimental and theoretical works, to analyze the spectroscopic composition of the samples, there are still many aspects which need to be investigated [6]. For example, Barthelemy et al. [22] investigated the influence of the laser parameters of an aluminum-induced plasma. They reported that the temperature slightly decreases at the plasma edge and close to the aluminum surface. This decrease in temperature at the plasma edge is basically caused by radiative cooling, while the decrease in temperature at the aluminum surface is as a result of thermal conduction. The authors also found that at the first microsecond of the ablation plume, the electron density was spatially homogeneous.Zhang et al.[23] also reported on the influence of laser parameters on plasma temperature. Their results predicted Abstract The magnesium plasma induced by a 1064-nm Q-switched Nd:YAG laser in atmospheric air was investigated. The evolution of the plasma was studied by acquiring spectral images at different laser energies and delay times. We observed that the intensities of the spectral lines decrease with larger delay times. The electron temperature was determined using the Boltzmann plot method. At a delay time of 100 ns and laser energy of 350 mJ, the electron temperature attained their highest value at 10164 K and then decreases slowly up to 8833.6 K at 500 ns. We found that the electron temperature of the magnesium plasma increases rapidly with increasing laser energy.

show abstract

Section: The Local Thermodynamic Equilibrium and The Optical Thinnessmentioning

confidence: 99%

Section: Theoretical Model Of the Electron Temperaturementioning

confidence: 99%

Influence of laser energy on the electron temperature of a laser-induced Mg plasma

Asamoah

Yao

2016

Appl. Phys. B

View full text Add to dashboard Cite

show abstract

“…The Boltzmann Plot method is based on the following straight line equation [1][2][3][4][5][6]33,34]:…”

Section: Determination Of Plasma Temperature and Number Densitymentioning

confidence: 99%

On the use of laser induced breakdown spectroscopy to characterize the naturally existing crystal in Pakistan and its optical emission spectrum

Iqbal

Mahmood

Tufail

et al. 2015

Spectrochimica Acta Part B: Atomic Spectroscopy

View full text Add to dashboard Cite

“…A good summary of further methods for determination of the plasma temperature is given by Zhang et al 35 Analysis of shock wave propagation and flame kernel formation…”

Section: Characterization Of Laser-induced Plasmamentioning

confidence: 99%

Pulse train ignition with passively Q-switched laser spark plugs

Lorenz

Bärwinkel

Stäglich

et al. 2015

International Journal of Engine Research

View full text Add to dashboard Cite

Leaner burning and downsizing are two concepts pursued by engine developers to reduce fuel consumption and emissions. Both approaches lead to increasing challenges concerning ignition, as these concepts are typically associated with an increase in flow velocity and degree of turbulence as well as raised pressure at the moment of ignition. In this context, the use of miniaturized passively Q-switched laser spark plugs with pulse train ignition is considered as a promising alternative to conventional spark plugs.However, the application of these passively Q-switched laser spark plugs inevitably leads to the question of optimum pulse train parameters. For a better understanding, this study deals with improved flame formation by passively Qswitched laser pulse train ignition under engine-like conditions. The entire ignition process is investigated with a special focus on interactions of consecutive pulses. Therefore, three methods are combined: energy transfer measurements from laser pulse to plasma with high temporal and spatial resolution show the breakdown process depending on different pressures and fluid mixtures. The temperature decrease in the induced plasma is analyzed with measurement strategies for temporal high-resolved plasma spectroscopy especially adapted to passively Q-switched lasers. In combination with high-speed schlieren measurements, the changing local ignition conditions during pulse train ignition are demonstrated. The experiments show how consecutive pulses interact and contribute to the ignition in case of a gas flow. The used prototypes of laser spark plugs are provided by Robert Bosch GmbH.

show abstract

Laser-induced plasma temperature

Cited by 149 publications

References 220 publications

Influence of laser energy on the electron temperature of a laser-induced Mg plasma

Influence of laser energy on the electron temperature of a laser-induced Mg plasma

On the use of laser induced breakdown spectroscopy to characterize the naturally existing crystal in Pakistan and its optical emission spectrum

Pulse train ignition with passively Q-switched laser spark plugs

Contact Info

Product

Resources

About