Excitation sources for fuel assembly vibrations in a PWR

Conference · Tue Jan 01 04:00:00 EST 1985

OSTI ID:5241318

Sweeney, F J; March-Leuba, J; Wood, R T; McNew, C O

Noise measurements from in-core neutron detectors have been utilized previously to monitor in-plant vibrations of pressurized water reactor (PWR) fuel assemblies. Fuel assembly resonant frequencies and mode shapes were obtained from these in-core measurements by observing resonances in the neutron noise power spectral density (PSD) and then plotting the axial dependence of the root mean square (rms) neutron noise over frequency ranges containing these resonances. In order to determine the fuel assembly mode shapes and their relationship to core barrel motion, we performed simultaneous measurements of in-core and ex-core neutron noise at the Sequoyah-1 reactor, a Westinghouse 1150 MW(e) PWR. Analysis of this data indicates that there are two different sources of vibrational excitation for the fuel in the 6- to 8-Hz frequency range. 7 refs., 2 figs.

• Research Organization: Oak Ridge National Lab., TN (USA); Tennessee Univ., Knoxville (USA)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5241318
• Report Number(s): CONF-850610-48; ON: TI85016405
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
210200* -- Power Reactors
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Light-Water Moderated
Nonboiling Water Cooled
ACOUSTIC MEASUREMENTS
DETECTION
ENRICHED URANIUM REACTORS
FREQUENCY RANGE
FUEL ASSEMBLIES
FUEL MOTION DETECTION
FUNCTIONS
HZ RANGE
IN CORE INSTRUMENTS
MEASURING INSTRUMENTS
MECHANICAL STRUCTURES
MECHANICAL VIBRATIONS
NEUTRON DETECTORS
POWER REACTORS
PWR TYPE REACTORS
RADIATION DETECTORS
REACTOR INSTRUMENTATION
REACTORS
SEQUOYAH-1 REACTOR
SPECTRAL DENSITY
SPECTRAL FUNCTIONS
SUPPORTS
THERMAL REACTORS
WATER COOLED REACTORS
WATER MODERATED REACTORS