Optical monitor for observing turbulent flow
Abstract
The present invention provides an apparatus and method for non-invasively monitoring turbulent fluid flows including anisotropic flows. The present invention uses an optical technique to filter out the rays travelling in a straight line, while transmitting rays with turbulence induced fluctuations in time. The output is two dimensional, and can provide data regarding the spectral intensity distribution, or a view of the turbulence in real time. The optical monitor of the present invention comprises a laser that produces a coherent output beam that is directed through a fluid flow, which phase-modulates the beam. The beam is applied to a temporal filter that filters out the rays in the beam that are straight, while substantially transmitting the fluctuating, turbulence-induced rays. The temporal filter includes a lens and a photorefractive crystal such as BaTiO.sub.3 that is positioned in the converging section of the beam near the focal plane. An imaging system is used to observe the filtered beam. The imaging system may take a photograph, or it may include a real time camera that is connected to a computer. The present invention may be used for many purposes including research and design in aeronautics, hydrodynamics, and combustion.
- Inventors:
-
- (Livermore, CA)
- (Rochester, NY)
- Issue Date:
- Research Org.:
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- OSTI Identifier:
- 868344
- Patent Number(s):
- 5121985
- Assignee:
- United States of America as represented by United States (Washington, DC) LLNL
- DOE Contract Number:
- W-7405-ENG-48
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- optical; monitor; observing; turbulent; flow; provides; apparatus; method; non-invasively; monitoring; fluid; flows; including; anisotropic; technique; filter; rays; travelling; straight; line; transmitting; turbulence; induced; fluctuations; time; output; dimensional; provide; data; regarding; spectral; intensity; distribution; view; comprises; laser; produces; coherent; beam; directed; phase-modulates; applied; temporal; filters; substantially; fluctuating; turbulence-induced; lens; photorefractive; crystal; batio; positioned; converging; section; near; focal; plane; imaging; observe; filtered; photograph; camera; connected; computer; purposes; design; aeronautics; hydrodynamics; combustion; output beam; fluid flow; focal plane; fluid flows; intensity distribution; turbulent flow; optical technique; optical monitor; straight line; converging section; data regarding; time camera; photorefractive crystal; /356/
Citation Formats
Albrecht, Georg F., and Moore, Thomas R. Optical monitor for observing turbulent flow. United States: N. p., 1992.
Web.
Albrecht, Georg F., & Moore, Thomas R. Optical monitor for observing turbulent flow. United States.
Albrecht, Georg F., and Moore, Thomas R. Wed .
"Optical monitor for observing turbulent flow". United States. https://www.osti.gov/servlets/purl/868344.
@article{osti_868344,
title = {Optical monitor for observing turbulent flow},
author = {Albrecht, Georg F. and Moore, Thomas R.},
abstractNote = {The present invention provides an apparatus and method for non-invasively monitoring turbulent fluid flows including anisotropic flows. The present invention uses an optical technique to filter out the rays travelling in a straight line, while transmitting rays with turbulence induced fluctuations in time. The output is two dimensional, and can provide data regarding the spectral intensity distribution, or a view of the turbulence in real time. The optical monitor of the present invention comprises a laser that produces a coherent output beam that is directed through a fluid flow, which phase-modulates the beam. The beam is applied to a temporal filter that filters out the rays in the beam that are straight, while substantially transmitting the fluctuating, turbulence-induced rays. The temporal filter includes a lens and a photorefractive crystal such as BaTiO.sub.3 that is positioned in the converging section of the beam near the focal plane. An imaging system is used to observe the filtered beam. The imaging system may take a photograph, or it may include a real time camera that is connected to a computer. The present invention may be used for many purposes including research and design in aeronautics, hydrodynamics, and combustion.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1992},
month = {1}
}