High speed UV laser induced fluorescence system for the detection of organic compounds using multi beam excitation

2003 ◽  
Author(s):  
V. Sivaprakasam ◽  
D.K. Killinger
Keyword(s):  
Organic Compounds ◽  
High Speed ◽  
Laser Induced Fluorescence ◽  
Uv Laser ◽  
Beam Excitation

High speed micromachining with high power UV laser

2013 ◽  
Author(s):  
Rajesh S. Patel ◽  
James M. Bovatsek
Keyword(s):  
High Power ◽  
High Speed ◽  
Uv Laser

Is UV laser induced fluorescence a method to monitor tropospheric OH?

1980 ◽  
Vol 7 (11) ◽  
pp. 905-908 ◽  
Author(s):  
G. Ortgies ◽  
K.-H. Gericke ◽  
F. J. Comes
Keyword(s):  
Laser Induced Fluorescence ◽  
Uv Laser

Film breakup of tilted impinging spray under various pressure conditions

2019 ◽  
Vol 21 (2) ◽  
pp. 330-339 ◽  
Author(s):  
Di Xiao ◽  
Ichikawa Yukihiko ◽  
Xuesong Li ◽  
David Hung ◽  
Keiya Nishida ◽  
...  
Keyword(s):  
Film Thickness ◽  
Boundary Conditions ◽  
Liquid Film ◽  
High Speed ◽  
Injection Pressure ◽  
Laser Induced Fluorescence ◽  
Parameter Study ◽  
Fluorescence Signal ◽  
Fuel Film ◽  
Various Boundary Conditions

Fuel film on engine walls caused by spray impingement would dramatically cause engine friction deterioration, incomplete combustion, and significant cycle-to-cycle variations. In a previous work, it has been demonstrated that fuel film would break up via wave entrainment induced by the high-speed coflow. Meanwhile, the film breakup dynamics depend on various boundary conditions, such as injection pressure, ambient pressure, and so on. However, such impact on the wall film formation was not investigated thoroughly in existing literature. This work aims to perform a parameter study to investigate possible means to enhance wave entrainment effect as to reduce the amount of impingement fuel mass. In this study, simultaneous measurements of macroscopic structure and its corresponding footprint of impinging spray are conducted using a single-hole, prototype injector in a constant volume chamber. The macroscopic spray structure was captured by high-speed backlit imaging, and the film was obtained using laser-induced fluorescence under different conditions. The laser-induced fluorescence signal is converted to film thickness following a calibration procedure where laser-induced fluorescence signals from a series of known-thickness film are captured. A mathematical processing method is used to analyze both the dynamic behavior of film thickness and amount of droplet detachment caused by high-speed coflow. It is found that at the leading edge of film waves, a remarkable amount of liquid droplets detaches from the liquid film and the quantity of film mass on the wall decreases during this process. Quantitative analysis is conducted and the mass ratio of detached droplets over residual liquid film is estimated. We hold that the film breakup percentage increases with both ambient and injection pressure due to the enhanced high-speed coflow. Then, variation laws for various boundary conditions are obtained based on the observations.

Kinematics of vortex ring generated by a drop upon impacting a liquid pool

2019 ◽  
Vol 875 ◽  
pp. 842-853 ◽  
Author(s):  
Abhishek Saha ◽  
Yanju Wei ◽  
Xiaoyu Tang ◽  
Chung K. Law
Keyword(s):  
Vortex Ring ◽  
High Speed ◽  
Morphological Evolution ◽  
Laser Induced Fluorescence ◽  
Liquid Pool ◽  
Viscous Effects ◽  
Penetration Process ◽  
Pool Surface ◽  
Three Stages ◽  
Unified Description

We herein report an experimental study on the morphological evolution of a vortex ring formed inside a liquid pool after it is impacted and penetrated by a coalescing drop of the same liquid. The dynamics of the penetrating vortex ring along with the deformation of the pool surface has been captured using simultaneous high-speed laser induced fluorescence and shadowgraph techniques. It is identified that the motion of such a vortex ring can be divided into three stages, during which inertial, capillary and viscous effects alternatingly play dominant roles to modulate the penetration process, resulting in linear, non-monotonic and decelerating motion in these three stages respectively. Furthermore, we also evaluate the relevant time and length scales of these three stages and subsequently propose a unified description of the downward motion of the penetrating vortex ring. Finally, we use the experimental data for a range of drop diameters and impact speeds to validate the proposed scaling.

Nitrogen laser induced fluorescence in laser dyes for sensing of organic compounds

2006 ◽  
Vol 113 (2) ◽  
pp. 805-808 ◽  
Author(s):  
Jagdish W. Dadge ◽  
V.N. Krishnamurthy ◽  
R.C. Aiyer
Keyword(s):  
Organic Compounds ◽  
Laser Induced Fluorescence ◽  
Nitrogen Laser ◽  
Laser Dyes

Carbon dioxide UV laser-induced fluorescence in high-pressure flames

2003 ◽  
Vol 375 (3-4) ◽  
pp. 344-349 ◽  
Author(s):  
W.G. Bessler ◽  
C. Schulz ◽  
T. Lee ◽  
J.B. Jeffries ◽  
R.K. Hanson
Keyword(s):  
Carbon Dioxide ◽  
High Pressure ◽  
Laser Induced Fluorescence ◽  
Uv Laser
Sign in / Sign up

Export Citation Format

Share Document