Method of and apparatus for measuring vapor density

Patent · Sun Jan 01 00:00:00 EST 1989

OSTI ID:867135

Nelson, Loren D ^[1]; Cerni, Todd A ^[2]

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1. Morrison, CO
2. Littleton, CO

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.

• Research Organization: Ophir Corp
• DOE Contract Number: AC03-83ER80090
• Assignee: Ophir Corporation (CO)
• Patent Number(s): US 4874572
• OSTI ID: 867135
• Country of Publication: United States
• Language: English

Related Subjects

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/