Ultrasonic measurement system with molecular weight determination
US6216091A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 24, 1999 |
| Grant date | Apr 10, 2001 |
| Priority date | — |
| Expiry date | Sep 24, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/2541
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An ultrasonic measurement system performs a signal path measurement by directing ultrasonic signals through a gaseous material in a conduit, and processing the detected signals to determine sound speed and to derive the average molecular weight of an unknown hydrocarbon mixture present in the material. The processor includes a plurality of stored tables of critical constants of hydrocarbon mixtures as a function of the average molecular weight of the mixture, and is configured to iteratively set a hypothetical molecular weight, determine the corresponding critical properties, and compute a predicted sound speed. If the two speeds differ, a new weight is set and the procedure is repeated until the predicted sound speed matches the measured speed, indicating that the current estimate is the correct average molecular weight. Once the processor has determined the critical constants from its stored tables, it applies the virial equation of state and mixing rules to determine the predicted sound speed for each hypothetical molecular weight of an unknown mixture of hydrocarbons present, together with one or more known inorganic components, in the fluid material. The processor may be confi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.