Velocity measurement system
US5226328A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 26, 1991 |
| Grant date | Jul 13, 1993 |
| Priority date | — |
| Expiry date | Jul 26, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S15/50
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sonic-type fluid flow measuring system wherein reflections or echoes of a burst 103 of ultrasonic energy from an ultrasonic acoustic emitter 9a are sensed and typically comprise a number of frequencies representative of a number of discrete velocities of flow in a volume of fluid. A receiver transducer 13a is gated to receive echoes from a selected volume of fluid 104 a selected distance from transducer 13a. Thereafter, this time domain signal sample is converted to a frequency domain sample whereby the presence and magnitude of each frequency component, or velocity component, is isolated, this being typically done by what is known as a Fast Fourier Transform unit 42a, obtaining a frequency domain waveform representative of average flow velocity. A variable noise threshold stored in register 52a is subtracted from the waveform to remove electronic noise, and the result integrated by integrator unit 54a to compensate for the return echoes returning from a slightly curved plane of the outwardly propagating wavefront. Seven of these samples are stored, and averaged by averaging-velocity translator unit 58a to obtain an average result, which is applied to averaging-velocity translato…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.