250 kW TRIGA Reactor

Introduction

The Maryland University Training Reactor (MUTR) is a very early model 250 kW General Atomics low enrichment uranium TRIGA reactor that was installed in 1970 as an upgrade from a 10 kW HEU Materials Testing Reactor previously installed in 1960. The UMD NRC license is #70 (Docket R-70). It is a major facility that supports teaching, research, and service for UMD as well as numerous outside collaborators.

Experimental Facilities

The MUTR is an open pool reactor with a maximum licensed, steady state, thermal power of 250 kW. The fuel is TRIGA-type stainless-steel-clad cylindrical fuel rods in which the enriched uranium is homogeneously mixed with a zirconium hydride neutron moderator. The MUTR is light water cooled and moderated, and the water also serves as a neutron reflector and biological shielding. The reactor contains five experimental facilities. The graphite filled thermal column provides an ex-core beam of thermal neutrons for experiments. Large samples, up to approximately 13.3 cm in diameter, can be placed adjacent to the core in either the beam tubes (two) or the through tube. The beam and through tubes can also provide ex-core gamma and neutron beams. Thermal flux levels in the through tube are 1.60 x 10^9 n/cm2/sec couple with a gamma dose rate of 2.1 rad/sec/kW. Finally, in-core irradiations of small samples (max. size of approx. 2.5 cm diameter by 5 cm length) can be performed using the pneumatic transfer system. This system is capable of providing thermal flux levels of 1.90 x 10^10 n/cm2/sec coupled with a gamma dose rate of 2.1 rad/sec/kW. Reactor power is monitored through three in-core neutron detectors: a fission chamber, a compensated ion chamber (CIC) and an uncompensated ion chamber.