Gas analyzer with background gas compensation
US6112576A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 1999 |
| Grant date | Sep 5, 2000 |
| Priority date | — |
| Expiry date | Sep 1, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/74
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sensor responds to a magnetic wind produced by the magnetic susceptibility of a target component gas, such as oxygen, which is present together with a background gas in a sample located in a measurement field produced in a measurement device. A background sampler also determines thermal and physical characteristics in a conditioned flow path, and a processor performs a computational correction on the detected magnetic wind signal to more accurately determine the concentration of the target gas. The background sampler includes a mass flow cell in series with a laminar flow device to measure heat capacity and viscous properties of the sample. It derives the gas viscosity from a differential pressure measurement; and preferably determines the heat capacity and thermal conductivity of background gases, the composition of which may be unknown, to compensate for their effects on the magnetic wind sensor elements. A further correction for diamagnetism of the background is made using one or more correlations between the measured parameters in certain common gases or classes of gases. The determination of gas bulk properties allows the concentration of the target gas to be made with enhan…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.