Single Primary Heat Extraction and Removal Emulator (SPHERE) Long Duration Testing

Sellers, Zachary Don [Idaho National Laboratory]; Hartvigsen, Jeremy Lee [Idaho National Laboratory] (ORCID:0000000293205552); Sabharwall, Piyush [Idaho National Laboratory] (ORCID:000000032567205X); Yilgor, Ilyas [Idaho National Laboratory] (ORCID:0000000169986662)

DOE OSTI · 3028398

Single Primary Heat Extraction and Removal Emulator (SPHERE) Long Duration Testing

Sellers, Zachary Don [Idaho National Laboratory]·Hartvigsen, Jeremy Lee [Idaho National Laboratory] (ORCID:0000000293205552)·Sabharwall, Piyush [Idaho National Laboratory] (ORCID:000000032567205X)·Yilgor, Ilyas [Idaho National Laboratory] (ORCID:0000000169986662)

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Abstract

For the development of heat-pipe cooled microreactors, it is crucial to thoroughly understand the characteristics and functioning of heat pipes across a wide spectrum of operating conditions. Passive heat removal and its long-term performance stability are critical factors in this context. Enhanced experimental data is vital for evaluating the operational lifespan of alkali metal heat pipes. Idaho National Laboratory (INL) has successfully conducted an extended duration test on a high-performance sodium-filled heat pipe, closely monitoring the axial temperature profile, power supplied by the heaters, and heat removed by a gas-gap calorimeter. The results from this testing provide valuable data that are instrumental in supporting heat pipe validation efforts. Specifically, this data aids in the development and validation of Sockeye, the Multiphysics Object-Oriented Simulation Environment (MOOSE) tool under the US-DOE NEAMS program designed for heat pipe modeling. By comparing experimental results with Sockeye’s predictions, the tool's accuracy and reliability can be assessed and improved, thereby enhancing its capability to simulate heat pipe operations under various conditions.

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Sellers, Zachary Don [Idaho National Laboratory], Hartvigsen, Jeremy Lee [Idaho National Laboratory] (ORCID:0000000293205552), Sabharwall, Piyush [Idaho National Laboratory] (ORCID:000000032567205X), Yilgor, Ilyas [Idaho National Laboratory] (ORCID:0000000169986662). 2025-09-05. Single Primary Heat Extraction and Removal Emulator (SPHERE) Long Duration Testing. https://www.osti.gov/biblio/3028398

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