Acousto-optical ultrasonic flowmeter
First Claim
1. Flowmeter apparatus for obtaining flow related data of a fluid flowing in a fluid conveyance comprising:
- (a) an optical window in the wall of said fluid conveyance;
(b) pulsed laser apparatus positioned to project a laser beam into said fluid through said optical window;
(c) said pulsed laser apparatus being of sufficiently high power density and short duration so as to cause a rapid thermal expansion of the fluid in the path of said beam, said thermal expansion generating a corresponding pressure wave, said beam within said conveyance acting as a line source of said pressure wave;
(d) first detecting means disposed from said beam and operable to detect said pressure wave as it passes, to provide a corresponding indication thereof;
(e) at least a second detecting means disposed from said beam and operable to detect said pressure wave as it passes, to provide a corresponding indication thereof;
(f) signal processing means responsive to said indications to provide said flow related data.
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Accused Products
Abstract
A flowmeter wherein measurements relating to fluid flowing in a pipe are obtained by transmitting a laser beam from a high power pulsed laser into the fluid through an optical window in the pipe. The beam in the fluid causes a rapid thermal expansion of the fluid which generates a pressure pulse which travels axially up and down the pipe. Continuously operating low power laser beams are projected into the fluid at points displaced from the source of the acoustic pulse and these beams are modulated when the acoustic pulse passes them. The modulation is detected to obtain first and second transit times, these transit times being utilized to compute the desired fluid flow parameters.
104 Citations
9 Claims
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1. Flowmeter apparatus for obtaining flow related data of a fluid flowing in a fluid conveyance comprising:
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(a) an optical window in the wall of said fluid conveyance; (b) pulsed laser apparatus positioned to project a laser beam into said fluid through said optical window; (c) said pulsed laser apparatus being of sufficiently high power density and short duration so as to cause a rapid thermal expansion of the fluid in the path of said beam, said thermal expansion generating a corresponding pressure wave, said beam within said conveyance acting as a line source of said pressure wave; (d) first detecting means disposed from said beam and operable to detect said pressure wave as it passes, to provide a corresponding indication thereof; (e) at least a second detecting means disposed from said beam and operable to detect said pressure wave as it passes, to provide a corresponding indication thereof; (f) signal processing means responsive to said indications to provide said flow related data. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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Specification