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Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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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.
Alessandro Annunziato
Nuclear Technology | Volume 96 | Number 2 | November 1991 | Pages 215-228
Technical Paper | Heat Transfer and Fluid Flow | doi.org/10.13182/NT91-A34607
Articles are hosted by Taylor and Francis Online.
Referring to single-phase natural circulation in steam generators with inverted U-tubes, various working conditions can be postulated in response to perturbations in the operating parameters. Clearly, such behavior is related to potential flow instabilities in parallel channels connected to a common manifold. A physical and analytical interpretation is given of the mechanism governing the onset and eventual divergence of flow surges observed in the LOBI-MOD2 steam generators during the evolution of thermal-hydraulic transients relevant to decay heat removal in pressurized water reactors. Secondary-side heat sink degradation is identified as the primary mechanism leading to the observed oscillations. A generalized analytical steady-state model is used to identify potential unstable operating conditions in the steam generators; a numerical method is then used to describe the transient condition.
