Method and apparatus for dew point determination
US5139344A · kind A · utility
Inventor
Key dates
| Filing date | Aug 12, 1991 |
| Grant date | Aug 18, 1992 |
| Priority date | — |
| Expiry date | Aug 12, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N25/68
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A new method for determination of the dew-point of a humid gas by means of a light beam reflected by a dew-point mirror. During measurements of dew-points, particularly in the range between -50.degree. C. to -95.degree. C., excess moisture is added to the humid gas under measurement in the manifold. Thus the dew-point mirror is for a short period of time, impacted with a humid gas of higher water content. This results in a fast build-up of a layer of dew on the mirror. In the subsequent process of dew-point determination, this reduces the time of measurement significantly. For carrying out the method, a dew-point measuring device is described, which comprises a manifold with a by-pass circuit having a gas valve, an injector unit and a humidification unit. Particularly useful in the device is a humidification unit made of hygroscopic polyamide tube which ensures maintenance-free humidification of the gas by the water molecules diffusing into this tube from the ambient atmosphere.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.