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Colin Judge: Testing structural materials in Idaho’s newest hot cell facility
Idaho National Laboratory’s newest facility—the Sample Preparation Laboratory (SPL)—sits across the road from the Hot Fuel Examination Facility (HFEF), which started operating in 1975. SPL will host the first new hot cells at INL’s Materials and Fuels Complex (MFC) in 50 years, giving INL researchers and partners new flexibility to test the structural properties of irradiated materials fresh from the Advanced Test Reactor (ATR) or from a partner’s facility.
Materials meant to withstand extreme conditions in fission or fusion power plants must be tested under similar conditions and pushed past their breaking points so performance and limitations can be understood and improved. Once irradiated, materials samples can be cut down to size in SPL and packaged for testing in other facilities at INL or other national laboratories, commercial labs, or universities. But they can also be subjected to extreme thermal or corrosive conditions and mechanical testing right in SPL, explains Colin Judge, who, as INL’s division director for nuclear materials performance, oversees SPL and other facilities at the MFC.
SPL won’t go “hot” until January 2026, but Judge spoke with NN staff writer Susan Gallier about its capabilities as his team was moving instruments into the new facility.
Tim H. J. J. van der Hagen
Nuclear Technology | Volume 83 | Number 2 | November 1988 | Pages 171-181
Technical Paper | Fission Reactor | doi.org/10.13182/NT88-A34158
Articles are hosted by Taylor and Francis Online.
The effective time constant related to heat transfer from fuel to coolant is a very important parameter for the dynamic behavior and thus the stability of a nuclear reactor. Usually a single time constant of a lumped parameter model is used. Both experimentally, via two independent methods of analysis, and theoretically, it is determined that a more elaborate model, using two or three time constants, is necessary. Heat transfer for high frequencies is governed by the small fuel time constants that stem from the outer region of the fuel. The bulk follows slow variations with time constants of >5 s.
