Acoustic wave (AW) based moisture sensor for use with corrosive gases

Patent · Mon Jan 01 04:00:00 EST 1996

OSTI ID:870677

Pfeifer, Kent B ^[1]; Frye, Gregory C ^[2]; Schneider, Thomas W ^[3]

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1. Los Lunas, NM
2. Cedar Crest, NM
3. Albuquerque, NM

Moisture corrosive gas stream is measured as a function of the difference in resonant frequencies between two acoustic wave (AW) devices, each with a film which accepts at least one of the components of the gas stream. One AW is located in the gas stream while the other is located outside the gas stream but in the same thermal environment. In one embodiment, the film is a hydrophilic material such as SiO.sub.2. In another embodiment, the SiO.sub.2 is covered with another film which is impermeable to the corrosive gas, such that the AW device in the gas stream measures only the water vapor. In yet another embodiment, the film comprises polyethylene oxide which is hydrophobic and measures only the partial pressure of the corrosive gas. Other embodiments allow for compensation of drift in the system.

• Research Organization: AT & T CORP
• DOE Contract Number: AC04-76DP00789
• Assignee: Sandia Corporation (Albuquerque, NM)
• Patent Number(s): US 5571944
• OSTI ID: 870677
• Country of Publication: United States
• Language: English

Related Subjects

/73/310/
accepts
acoustic
acoustic wave
allow
based
compensation
components
comprises
comprises poly
corrosive
corrosive gas
corrosive gases
covered
device
devices
difference
drift
embodiment
embodiments
environment
film
film comprises
frequencies
function
gas
gas stream
gases
hydrophilic
hydrophobic
impermeable
located
located outside
material
measured
measures
moisture
moisture sensor
outside
oxide
partial
partial pressure
polyethylene
polyethylene oxide
pressure
resonant
resonant frequencies
sensor
sio
stream
thermal
vapor
water
water vapor
wave