Thermal measuring and testing – Transformation point determination – Between gaseous and liquid states
Patent
1993-04-16
1994-11-15
Gutierrez, Diego F. F.
Thermal measuring and testing
Transformation point determination
Between gaseous and liquid states
73 2902, G01N 2568, G01N 2502
Patent
active
053641850
ABSTRACT:
An uncoated interdigitated transducer is cooled from a temperature above the dew point to a temperature below the dew point, while a parameter of a signal of the transducer is measured. The reduction in temperature causes a monotonic change in transducer signal because that signal is sensitive primarily to the water loading of the transducer surface as water forms on that surface due to the reduction in temperature. As the dew point is approached with temperature reduction, the slope of the curve of transducer signal with respect to temperature, remains relatively constant. However, as the dew point is reached the slope of that curve increases and because of changes in the structure of the water layer on the surface of the transducer, at the dew point the transducer responds with a clear shift in the rate at which the transducer signal changes. The temperature at which the second derivative of signal vs. temperature peaks can be readily used to identify with extreme accuracy, the precise dew point. The measurement technique employed by the present invention is relatively immune to surface contamination which remains significantly unchanged during the brief measurement period.
REFERENCES:
patent: 4378168 (1983-03-01), Kuisma et al.
patent: 4589274 (1986-05-01), Boyle et al.
patent: 4626774 (1986-12-01), Regtien
patent: 4877329 (1989-10-01), Sauerbaum et al.
patent: 4898476 (1990-02-01), Herrmann et al.
patent: 4948263 (1990-08-01), Herrmann et al.
Hygrometery by H. Spencer-Gregory and E. Rourke, published by Pitman Publishing Company.
Crisp David
Kaiser William J.
Kenny Thomas W.
VanZandt Thomas R.
California Institute of Technology
Gutierrez Diego F. F.
Tachner Leonard
LandOfFree
High performance miniature hygrometer and method thereof does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with High performance miniature hygrometer and method thereof, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and High performance miniature hygrometer and method thereof will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1092921