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US 7,581,877 B1Granted
Apparatus and method for measuring the dew point of gases using spectral recognition of the condensate
AssigneeSohrab Zarrabian
InventorSohrab Zarrabian
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AssigneeSohrab Zarrabian
InventorSohrab Zarrabian
Estimating the term…
A new method and apparatus is described for measurement of the dew point, and thus the vapor pressure of various gases and gas mixtures. In this method an optical element which is exposed to a gas atmosphere is cooled while its temperature is being monitored. At the same time an optical signal is sent through the back of the optical element. The optical signal goes through internal reflections. As soon as dew forms on the surface of the element, the optical signal will exhibit selective absorption due to the interaction of the evanescent tail of the optical signal and based on the chemical nature of the condensate. This invention can also be used to characterize condensable content of gas mixtures. The method allows for the spectral characterization and determination of the condensed vapor. It offers several advantages over existing methods.
An apparatus for measuring dew point of gases using spectral measurement or recognition of condensate, said apparatus comprising:
An optical element which is exposed to a quantity of gas, and the said optical element is cooled, leading to the condensation of liquid on its surfaces, and where an optical signal enters the said optical element, and is incident upon the internal surface of the said optical element at an angle which causes the optical signal to undergoing total internal reflection in the optical element, one or several times, and then exits the optical element where its spectral content is measured using a spectrometer, or one or several optical filters in combination with detectors, and where the temperature of the surface where condensation takes place is monitored by temperature sensing devices, the pressure of the gas is monitored using pressure sensing devices, and the element is periodically cooled and heated to cause condensation and then evaporation of condensate.
Dependencies are inferred from the claim text.