scholarly journals Equivalence Ratio Measurements in CH4/Air Gases Based on the Spatial Distribution of the Emission Intensity of Femtosecond Laser-Induced Filament

Processes ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 2022
Author(s):  
Ming Li ◽  
Jiangpeng Gu ◽  
Dayuan Zhang ◽  
Qiang Gao ◽  
Bo Li
Keyword(s):  
Spatial Distribution ◽  
Flow Field ◽  
Femtosecond Laser ◽  
Emission Intensity ◽  
Equivalence Ratio ◽  
Femtosecond Lasers ◽  
Diagnostic Techniques ◽  
Spatially Resolved ◽  
Combustion Diagnostics ◽  
Laser Filamentation

Femtosecond lasers have been used in combustion diagnostics. Based on the characteristics of femtosecond laser filamentation, many diagnostic techniques have been developed. Here, we propose a method, based on femtosecond laser filamentation, for equivalence ratio measurements in CH4/air gases. By measuring the spatially resolved spectra of the femtosecond laser-induced filament, we found that the variation of the equivalence ratio in the flow field would affect the spatial distribution of the emission intensity of femtosecond laser-induced filament. On this basis, the equivalence ratio was calibrated by using the relative spatial positions of N2 (337 nm) and C2 (516.5 nm) signals in the filament. This method overcomes the interference of local air disturbance, having lower measurement uncertainty.

scholarly journals A Review of Femtosecond Laser-Induced Emission Techniques for Combustion and Flow Field Diagnostics

2019 ◽  
Vol 9 (9) ◽  
pp. 1906 ◽  
Author(s):  
Bo Li ◽  
Dayuan Zhang ◽  
Jixu Liu ◽  
Yifu Tian ◽  
Qiang Gao ◽  
...  
Keyword(s):  
Flow Field ◽  
Femtosecond Laser ◽  
Femtosecond Lasers ◽  
Diagnostic Techniques ◽  
Nonlinear Spectroscopy ◽  
Plasma Spectroscopy ◽  
Breakdown Spectroscopy ◽  
Two Photon ◽  
Combustion Diagnostics ◽  
Laser Induced Breakdown

The applications of femtosecond lasers to the diagnostics of combustion and flow field have recently attracted increasing interest. Many novel spectroscopic methods have been developed in obtaining non-intrusive measurements of temperature, velocity, and species concentrations with unprecedented possibilities. In this paper, several applications of femtosecond-laser-based incoherent techniques in the field of combustion diagnostics were reviewed, including two-photon femtosecond laser-induced fluorescence (fs-TPLIF), femtosecond laser-induced breakdown spectroscopy (fs-LIBS), filament-induced nonlinear spectroscopy (FINS), femtosecond laser-induced plasma spectroscopy (FLIPS), femtosecond laser electronic excitation tagging velocimetry (FLEET), femtosecond laser-induced cyano chemiluminescence (FLICC), and filamentary anemometry using femtosecond laser-extended electric discharge (FALED). Furthermore, prospects of the femtosecond-laser-based combustion diagnostic techniques in the future were analyzed and discussed to provide a reference for the relevant researchers.

scholarly journals Spatial distribution of nitrogen fluorescence emission induced by femtosecond laser filamentation in air

2021 ◽  
Vol 70 (13) ◽  
pp. 134206
Author(s):  
Yun Zhang ◽  
Shuang Lin ◽  
Yun-Feng Zhang ◽  
He Zhang ◽  
Ming-Ying Chang ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Femtosecond Laser ◽  
Fluorescence Emission ◽  
Laser Filamentation

Spatial distribution of the fluorescence induced by femtosecond laser filamentation in ambient air

2020 ◽  
Vol 131 ◽  
pp. 106417
Author(s):  
Jiabin Wu ◽  
Zhiyong Wu ◽  
Tao Chen ◽  
He Zhang ◽  
Yunfeng Zhang ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Femtosecond Laser ◽  
Ambient Air ◽  
Laser Filamentation

External focusing dependence of spatial distribution of air lasers during femtosecond laser filamentation in air

2021 ◽  
Vol 19 (8) ◽  
pp. 081402
Author(s):  
Jiayun Xue ◽  
Hui Gao ◽  
Nan Zhang ◽  
Lu Sun ◽  
Lie Lin ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Femtosecond Laser ◽  
Laser Filamentation

Gaseous pre-lattice assisted supercontinuum enhancement of femtosecond laser filamentation

2021 ◽  
Vol 28 (7) ◽  
pp. 072303
Author(s):  
Yajun Guo ◽  
Jianji Wang ◽  
Xiaowei Song ◽  
Jingquan Lin
Keyword(s):  
Femtosecond Laser ◽  
Laser Filamentation

scholarly journals Titanium surface modification using femtosecond laser with 1013–1015 W/cm2 intensity in vacuum

2012 ◽  
Vol 31 (1) ◽  
pp. 29-36 ◽  
Author(s):  
M. Trtica ◽  
D. Batani ◽  
R. Redaelli ◽  
J. Limpouch ◽  
V. Kmetik ◽  
...  
Keyword(s):  
Surface Modification ◽  
Femtosecond Laser ◽  
Titanium Surface ◽  
Femtosecond Lasers ◽  
Single Pulse ◽  
Surface Structures ◽  
Pulse Regime ◽  
Periodic Surface ◽  
Reduced Intensity ◽  
Surface Changes

AbstractThe response of titanium surface irradiated with high intensity (1013 – 1015 W/cm2) Ti:sapphire laser was studied in vacuum. Most of the reported investigations were conducted with nano- to femtosecond lasers in gas atmospheres while the studies of titanium surface interacting with femtosecond laser in vacuum are scarce. The laser employed in our experiment was operating at 800 nm wavelength and pulse duration of 60 fs in single pulse regime. The observed surface changes and phenomena are (1) creation of craters, (2) formation of periodic surface structures at the reduced intensity, and (3) occurrence of plasma in front the target. Since microstructuring of titanium is very interesting in many areas (industry, medicine), it can be concluded from this study that the reported laser intensities can effectively be applied for micromachining of the titanium surface (increasing the roughness, formation of parallel periodic surface structures etc.).

Sign in / Sign up

Export Citation Format

Share Document