Results of Sefor Zero Power Experiments.

Abstract

The SEFOR experimental program is comprised of a series of tests beginning with low power tests, proceeding through static and frequency response tests at various power levels up to full power, and culminating in a series of sub-prompt and super-prompt critical transients. The results of the low (zero) power tests are reported here and are compared with calculations. The agreement between experiment and calculation is generally good. The tests were conducted at low power and included such experiments as the approach to the minimum critical core size, calibration of the reflector control, measurement of fission rate distributions, material reactivity worth measurements, uniform non-nuclear heating of the reactor to determine the reactivity temperature coefficient, and the measurement of the ratio (Jl/3) of the prompt neutron lifetime to the effective delayed neutron fraction.

SOUTHWEST EXPERIMENTAL FAST OXIDE REACTOR DEVELOPMENT PROGRAM. Twenty- Eighth Quarterly Report, February--April 1971.

“…Comparison of the results with calculations demonstrated that the Doppler component of the feedback can be described by a fuel temperature coeffic1~nt T(dk/dT) of ~.0081 with an estimated standard deviation of ±0.0014. This coefficient compares favorably with the value* of ~.0085 that was predicted 2 prior to the measurements. * This is the estimated predictiOn for ·the cores, Assemblies 1-1 and 1-J (the present core), on which these Doppler experiments were performed.…”

Review of the analyses of the Doppler-effect measurements in SEFOR (Southwest Experimental Fast Oxide Reactor)

“…It is therefore important to consider the magnitude of the error in the Doppler coefficient as such in addition to a comparison of AkD, (7). Table III Table III.…”