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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.
Syed Hameed Qaiser, Masood Iqbal, Aamer Iqbal Bhatti, Raza Samar, Javed Qadir
Nuclear Science and Engineering | Volume 172 | Number 3 | November 2012 | Pages 327-336
Technical Paper | doi.org/10.13182/NSE11-46
Articles are hosted by Taylor and Francis Online.
This paper discusses a higher-order sliding-mode-observer design for estimating reactivity in a nuclear research reactor. The nonlinear model of the Pakistan Research Reactor-1 (PARR-1) has been tuned and validated with experimental data. This model is then used for higher-order sliding-mode-observer-based reactivity estimation. In thermal reactors, reactivity is a very important reactor variable, as it determines the change of output power variation and is the main variable being manipulated for reactor power control. Linear observers have been used in the past to estimate reactivity, but the bandwidth is limited, and performance gets degraded as the operating point is changed. A nonlinear observer can efficiently address this problem. In this paper a robust higher-order sliding-mode observer is employed to estimate this variable. The higher-order sliding-mode observer is efficient and has the main advantage of reduced chattering. The estimators predict this variable with the measurement of neutron flux only. The estimated value is in close agreement with the theoretically calculated value.
