Guarded capacitance probes for measuring particle concentration and flow

Patent · Sun Jan 01 00:00:00 EST 1995

OSTI ID:870121

Louge, Michel Y ^[1]

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1. Ithaca, NY

Guarded capacitance probe structures are constructed with guard electrodes surrounding one or more sensor electrodes and ground electrodes or grounded surfaces surrounding the guard electrodes. In a one sensor embodiment, the probe utilizes an apertured sensor electrode and the guard electrode both surrounds the sensor electrode and fills the aperture. This embodiment is particularly useful for measuring particle concentration in a fluid suspension contained within a vessel or pipe. The portion of the guard electrode within the aperture of the sensor electrode prevents electric field lines from emanating from the sensor electrode into the fluid suspension and toward infinity. A two sensor embodiment of the probe is useful for measuring flow velocities of fluid suspensions through cross correlation of the outputs generated by each sensor. The relative dimensions of the guard and sensor electrodes are selected to provide the most accurate measurements by confining the electric lines emanating from the sensor electrode or electrodes and terminating on the surrounding grounded surfaces to a small measurement volume of the fluid suspension near the vessel or pipe wall.

• Research Organization: Cornell Univ., Ithaca, NY (United States)
• DOE Contract Number: AC22-91PC90183
• Assignee: Cornell Research Foundation, Inc. (Ithaca, NY)
• Patent Number(s): US 5459406
• OSTI ID: 870121
• Country of Publication: United States
• Language: English

Related Subjects

guarded
capacitance
probes
measuring
particle
concentration
flow
probe
structures
constructed
guard
electrodes
surrounding
sensor
ground
grounded
surfaces
embodiment
utilizes
apertured
electrode
surrounds
fills
aperture
particularly
useful
fluid
suspension
contained
vessel
pipe
portion
prevents
electric
field
lines
emanating
infinity
velocities
suspensions
correlation
outputs
generated
relative
dimensions
selected
provide
accurate
measurements
confining
terminating
measurement
volume
near
wall
accurate measurements
flow velocities
probe utilizes
guard electrode
sensor electrode
field lines
electric field
particularly useful
ground electrode
particle concentration
measuring particle
accurate measurement
surrounding grounded
surfaces surrounding
capacitance probe
prevents electric
outputs generated
measuring flow
sensor electrodes
guarded capacitance
guard electrodes
grounded surfaces
pipe wall
ground electrodes
electrodes surrounding
accurate measure
surrounding ground
rate measurements
capacitance probes
probe structures
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