Stream-cleaned differential reflection coefficient sensor
US6330831A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 18, 1999 |
| Grant date | Dec 18, 2001 |
| Priority date | — |
| Expiry date | Oct 18, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/02881
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An ultrasonic system employs a path through a fluid to determine fluid density by a differential reflection coefficient measurement of fluid impedance Z and a fluid sound speed c. Preferred configurations use clamp-on (external) transducers and combine ultrasonic measurements of flow velocity V over one or more paths, to obtain the mass flow rate. Z is determined by comparing reflections from a reference target, which may be totally reflective, with reflections from a sensor target having an effectively lower Z, which may be close to that of the fluid. Both targets are preferably located to be cleaned by the natural flow of the fluid. The low-Z target is interrogated at least once. Vee blocks provide a compact combination of reference and sensor targets that can be integrated with a velocity-sensing flowcell. Folded-path flow cells compactly measure V alone or in combination with density. The principal surface may be aligned parallel to the free stream direction and located to yield a flow value substantially equal to the area averaged flow, and the system may further correct for variations in the vicinity of the reflector.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.