DYNAMIC VOID FRACTION MEASUREMENT SYSTEM

Technical Report · Wed May 15 00:00:00 EDT 1963

DOI:https://doi.org/10.2172/4710826· OSTI ID:4710826

Kendron, J H; Stoner, E E; Taylor, G M

Various methods and techniques of measuring void fraction in boiling heat transfer media are discussed. Details of 17 void-fraction measurement systems are abstracted. A dynamic void-fraction measurement system is described, capable of continuously measuring void fraction at any position along a 12-ft test section. Void fraction (the ratio of vapor volume to total volume of a 2- phase mixture) is measured in boiling organic coolant contained by a test section of 5/8-in.-OD nickel tube with 0.049-in. wall thickness. Measurement of void fraction without physical contact with the test section is achieved through the use of a radiation attenuation method. The intensity of a narrow 100-kev x-ray beam transmitted through the test section is measured and recorded to permit calculation of void fraction. An x-ray tube and scintillation detectors are mounted on a remotely controlled elevator assembly used for horizontal and vertical positioning. Major sources of measurement error due to fluctuations in x-ray tube output and fluctuation of detector power supply voltage are cancelled by using two detectors connected in a differential circuit. Detector cooling and heavy magnetic shielding further reduce measurement errors. Typical measurement accuracies for small and large void fractions are 0.05 surface proces 0.015 and 1.00 surface proces 0.022. (auth)

• Research Organization: Atomics International. Div. of North American Aviation, Inc., Canoga Park, Calif.
• DOE Contract Number: AT(11-1)-GEN-8
• NSA Number: NSA-17-025410
• OSTI ID: 4710826
• Report Number(s): NAA-SR-7875
• Resource Relation: Other Information: Orig. Receipt Date: 31-DEC-63
• Country of Publication: United States
• Language: English

Related Subjects

ENGINEERING AND EQUIPMENT
ABSORPTION
BEAMS
BOILING
COINCIDENCE METHODS
COOLING
ELECTRON TUBES
ELECTRONIC EQUIPMENT
ENERGY LEVELS
ERRORS
FLUIDS
HEAT TRANSFER
LABORATORY EQUIPMENT
LIQUIDS
MAGNETIC FIELDS
MATHEMATICS
MEASURED VALUES
MECHANICAL STRUCTURES
NICKEL
ORGANIC COMPOUNDS
PERFORMANCE
POWER
RADIATION DETECTORS
RADIATION DOSES
RECORDING SYSTEMS
SCINTILLATION COUNTERS
SERVOMECHANISMS
SURFACES
THICKNESS
TUBES
VAPORS
VARIATIONS
VOID FRACTION
X RADIATION