Special TIP and gamma Scan Comparisons from Hatch-1. Comparisons of Simulated Process Computer Thermal Neutron TIP and gamma TIP Calculations with gamma Scan Measurements at Edwin I. Hatch Nuclear Plant, Unit 1 at End of Cycle 1.

摘要

Experimental measurements using gamma scanning techniques were performed at the Edwin I. Hatch Nuclear Plant, Unit 1, at the end of Cycle 1. These data are indicative of the power distribution in the reactor prior to shutdown. This report compares axial, radial, and nodal BA-140 fission-product (related to power) distributions, TIP asymmetries, and control blade effects between the thermal neutron TIP (traversing in-core probe), gamma sensitive TIP, and the gamma scan measurements. Relative to the thermal neutron TIP, calculated power distribution comparisons show that the gamma-sensitive TIP significantly reduces the apparent nodal and bundle power asymmetries. This reduction in asymmetry contributes to a 3% increase in the gamma TIP calculated thermal margins. Both the thermal neutron and gamma TIP calculated thermal margins were found to be conservative relative to the gamma scan measurements.