Resources Contact Us Home
Optical flow rate measurement using unsteady pressures

Image Number 11 for United States Patent #6536291.

A fiber optic strain gauge based flow rate measurement system includes two measurement regions located an average axial distance .DELTA.X apart along the pipe, the first measurement region having two fiber optic strain gauges located a distance X.sub.1 apart, and the second measurement region having two other fiber optic strain gauges located a distance X.sub.2 apart, each capable of measuring the unsteady pressure in the pipe 12. Signals from each pair of fiber optic strain gauges are differenced by summers to form spatial wavelength filters. Each spatial filter filters out acoustic pressure disturbances P.sub.acoustic and other long wavelength pressure disturbances in the pipe and passes short-wavelength low-frequency vortical pressure disturbances P.sub.vortical associated with the vortical flow field. The spatial filters provide signals to band pass filters that filter out high frequency signals. The P.sub.vortical -dominated filtered signals from the two sensing regions are cross-correlated to determine a time delay .tau. between the two sensing locations which is divided into the distance .DELTA.X to obtain a convection velocity U.sub.c (t) that is related to an average flow rate of the fluid (i.e., one or more liquids and/or gases) flowing in the pipe 12. The invention may also be configured detect the velocity of any desired inhomogeneous pressure field in the flow.

  Recently Added Patents
System and method for detecting executable machine instructions in a data stream
Hybrid interconnect scheme including aluminum metal line in low-k dielectric
Heating pad
Electronic component and a system and method for producing an electronic component
Medicament container
Maize variety hybrid X13A495
Compact semiconductor memory device having reduced number of contacts, methods of operating and methods of making
  Randomly Featured Patents
Locking frame, filter and deployment system
Flat coil element for an electric motor and method of manufacturing the same
Co-micronized bicarbonate salt compositions
Comb filter circuit
Antibodies to train R: a cysteine-rich member of the TNF-receptor family, and methods of treating tumors expressing said receptor
Dual stage source/sink amplifier circuit with quiescent current determination
Photochromic heterocyclically anellated indenochromene compounds
Toilet seat with handle
Ride-on toy vehicle
Process for purifying lactams