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Title: Method of and apparatus for measuring vapor density

Abstract

Apparatus and method determine the concentration of an individual component, such as water vapor, of a multi-component mixture, such as a gaseous mixture for cooling a nuclear reactor. A hygrometer apparatus includes an infrared source for producing a broadband infrared energy beam that includes a strong water vapor absorption band and a weak water vapor absorption region. The beam is chopped to select infrared pulses. A temporally first pulse has a wavelength in the weakly absorbing region, a temporally second pulse has a wavelength in the strong band and a temporally third pulse has a wavlength in the weakly absorbing region. A fourth reference pulse representing background radiation is interposed in such chopped pulses. An indium arsenide infrared sensor is responsive to the pulses for generating an output signal in proportion to: ##EQU1## where N1 is proportional to the transmission through the sample of the first signal, N4 is related to the background radiation, and [K2 (N2-N4)+K3 (N3-N4)] is the time-weighted average of the transmission through the sample of the second and third pulses applicable at the time of the second pulse, with the reference pulse N4 being subtracted in each case to render the ratio independent of variations inmore » the background radiation.

Inventors:
 [1];  [2]
  1. Morrison, CO
  2. Littleton, CO
Issue Date:
Research Org.:
Ophir Corp
OSTI Identifier:
867135
Patent Number(s):
4874572
Assignee:
Ophir Corporation (CO)
Patent Classifications (CPCs):
G - PHYSICS G01 - MEASURING G01J - MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRA-RED, VISIBLE OR ULTRA-VIOLET LIGHT
G - PHYSICS G01 - MEASURING G01N - INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
DOE Contract Number:  
AC03-83ER80090
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
method; apparatus; measuring; vapor; density; determine; concentration; individual; component; water; multi-component; mixture; gaseous; cooling; nuclear; reactor; hygrometer; infrared; source; producing; broadband; energy; beam; strong; absorption; band; weak; region; chopped; select; pulses; temporally; pulse; wavelength; weakly; absorbing; third; wavlength; fourth; reference; representing; background; radiation; interposed; indium; arsenide; sensor; responsive; generating; output; signal; proportion; equ1; n1; proportional; transmission; sample; n4; related; k2; n2-n4; k3; n3-n4; time-weighted; average; applicable; time; subtracted; render; ratio; independent; variations; absorption band; energy beam; background radiation; absorbing region; reference pulse; infrared energy; water vapor; gaseous mixture; nuclear reactor; output signal; vapor density; multi-component mixture; infrared source; individual component; /376/250/976/

Citation Formats

Nelson, Loren D, and Cerni, Todd A. Method of and apparatus for measuring vapor density. United States: N. p., 1989. Web.
Nelson, Loren D, & Cerni, Todd A. Method of and apparatus for measuring vapor density. United States.
Nelson, Loren D, and Cerni, Todd A. Sun . "Method of and apparatus for measuring vapor density". United States. https://www.osti.gov/servlets/purl/867135.
@article{osti_867135,
title = {Method of and apparatus for measuring vapor density},
author = {Nelson, Loren D and Cerni, Todd A},
abstractNote = {Apparatus and method determine the concentration of an individual component, such as water vapor, of a multi-component mixture, such as a gaseous mixture for cooling a nuclear reactor. A hygrometer apparatus includes an infrared source for producing a broadband infrared energy beam that includes a strong water vapor absorption band and a weak water vapor absorption region. The beam is chopped to select infrared pulses. A temporally first pulse has a wavelength in the weakly absorbing region, a temporally second pulse has a wavelength in the strong band and a temporally third pulse has a wavlength in the weakly absorbing region. A fourth reference pulse representing background radiation is interposed in such chopped pulses. An indium arsenide infrared sensor is responsive to the pulses for generating an output signal in proportion to: ##EQU1## where N1 is proportional to the transmission through the sample of the first signal, N4 is related to the background radiation, and [K2 (N2-N4)+K3 (N3-N4)] is the time-weighted average of the transmission through the sample of the second and third pulses applicable at the time of the second pulse, with the reference pulse N4 being subtracted in each case to render the ratio independent of variations in the background radiation.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 1989},
month = {Sun Jan 01 00:00:00 EST 1989}
}