"An analytical model was developed in order to accurately estimate the dose rates in air of the highly-enriched uranium (HEU) fuel at the University of Missouri - Rolla Reactor. Based upon these results, a method is proposed to remove the fuel from the reactor.
First thermoluminescent dosimeters (TLDs) were exposed under water to each of the fuel elements in the reactor pool, except for the four control rodded elements. A model was developed to use the in-water TLD readings to calculate the dose rate of the fuel elements in air at 1 foot and 3 feet. The fuel was modeled first as a cylindrical source; then as a line source. Since both models seemed to underestimate the source strength of the fuel, each of the fuel elements were then approximated as a line source with a cosine distribution along the line. Once the dose rates in air had been predicted, a single element was removed from the pool, and TLDs were exposed to the element to determine the actual in-air reading. The cosine distributed line source appeared to be somewhat of an overestimate; thus the results it gave were conservative in determining the strength of the source. Since the model yielded good results, it was adopted for all of the elements.
Fuel element F9 had the highest dose rate which was calculated to be 54.7 rem/hr +/- 10% at 1 foot and 18.1 rem/hr +/- 10% at 3 feet in air. Based on the high dose rate of this element, and several others, it was decided that the transporting of the elements could be broken down into two shipments with the least radioactive being taken on the first trip: then removing and shipping the others after storage in the spent fuel pool for a year or more"--Abstract p. iii
Albert E. Bolon
Louis J. Grimm
Nuclear Engineering and Radiation Science
M.S. in Nuclear Engineering
University of Missouri--Rolla
viii, 56 pages
© 1991 Alice Ann Netzer, All rights reserved.
Thesis - Open Access
Print OCLC #
Netzer, Alice Ann, "Dose rate determination of the highly-enriched uranium fuel at the University of Missouri-Rolla Reactor in preparation for transportation" (1991). Masters Theses. 1016.