b"Massachusetts Institute of Technology Reactor (MITR) High-Temperature Water Loop DesignPrincipal Investigator: Kouroush ShirvanTeam Members/Collaborators: Nicolas WoolstenhulmeT he Massachusetts Institute ofThese slots utilize the core's full Technology Reactor (MITR)18-inch height, plus some overhead, provides advanced capabili- with a 2-inch diameter envelope ties for fuel cladding testing, particu- inside each dummy fuel element for larly with its High Temperatureencapsulating irradiation vehicles. Water Loop designed for boilingPresently, MITR's lab runs the High water reactor (BWR) conditions.Temperature Water Loop (HTWL), This article delves into MITR'san in-core pressurized water loop existing facilities and introduces thein one of the in-core experimental recent addition of a high-pressurelocations. It simulates prototypical water loop further enhancing itsBWR conditions, heating specimens capacity for pressurized waterup to 300C, restricted mainly by the reactor (PWR) environment testing. autoclave's in-vessel pressure rating (~10.3 MPa at present). All loop Capability Description: operations, from flow and heating to The MIT Nuclear Reactor Lab (NRL)sampling, occur outside the primary offers a comprehensive set of irradia- reactor vessel. The in-vessel part tion experiment support, spanningpositions samples in the core's peak vehicle design, fabrication, opera- neutron flux zone or gamma-only tion, to post-irradiation analysissections above the core. This loop is and shipping. The 6 MW MITRbeing extensively used for materials' can accommodate three primarycorrosion, irradiation behavior, and in-core irradiation vehicles, supple- real-time instrument testing. Typical mented by reflector and beamlinesamples in this setup include irradiation positions. Addition- fuel cladding, corrosion tests, and ally, pneumatic facilities cater toisothermal specimens at light water irradiations on smaller samplesreactor temperatures, generally up and conduct neutron activationto 11 mm wide and 200 mm long. analysis for safety reviews beforeVarious specimens and sensors can in-core irradiation. The three maincoexist, that provide temperature, in-core positions at the MITR boast impressive neutron fluxes: 3.5x10 13 neutron flux and electrochemical thermal, 1.1x10 14E0.1 MeV n/cm 2 -s,potential mapping. The capsule and around 1x10 9R/hr gamma.assembly is adaptable per cycle, ensuring alignment with project 20 2023|AFC ACCOMPLISHMENTS"