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Argonne’s pressure drop experimental loop for investigation of core assemblies in advanced nuclear reactors (PELICAN) generates verification and validation data for modern reactor designs.

PELICAN, the Pressure Drop Experimental Loop for Investigations of Core Assemblies in Advanced Nuclear Reactors, is a novel experimental facility designed and constructed at Argonne National Laboratory to recreate the hydraulic flow conditions for the Versatile Test Reactor (VTR) currently under development by the U.S. Department of Energy.

The VTR will rely on fast neutrons to enable new and wide-ranging experiments to support development of the various advanced reactor technologies. With the high flux achievable, accelerated testing of fuel and materials will be made possible. To support VTR design efforts, PELICAN is used to replicate VTR’s primary heat transport system (PHTS) and the measurement objectives for data generated from this test facility are driven primarily by the validation needs for code calculations and simulations of the reference VTR core. These objectives focus on the need to validate pressure drop results across the various segments of the fuel assembly, including the axial reflectors, fuel, and transition regions, as they relate directly to the pumping power and safety behavior of the reactor. Critical to accurately representing the physical flow fields is empirical knowledge of Reynolds number (Re) and pressure drop (ΔP). Furthermore, the conditions and thermohydraulic state of the flowing coolant must be known to ensure that material properties can be accurately captured by computational models.

Control and Data Acquisition Program

Collectively, these parameters can be obtained by the current suite of sensors within the PELICAN loop, which include the use of a volumetric flow meter, thermocouples, and pressure transmitters. These have been selected to provide measurements of pertinent thermal and hydraulic properties across the range of conditions planned for the various testing activities. These sensors are able to accurately measure the physical flow fields in a fashion that is non-invasive and does not influence the normal flow behavior.

Hexagonal Test Section and Various Test Articles

An initial testing campaign focused on the commissioning of the new device, facility characterization that assesses the operational capabilities of the control and acquisition systems, and the first phase of experimental testing. During this first phase of testing, various orifice plates were used as simple test articles for which a known and measurable pressure drop can be generated as a function of flowrate. Using these orifice plates first provided both a means of validating the experimental facility and a simple geometry from which comparative flow simulations can be performed. Beginning in March 2021, the experimental testing phase will shift from orifice plates to test articles designed, fabricated, and tested for VTR.

PELICAN at a glance

  • Test Section Cavity60400 cm length, 11.1 cm side to side hexagon
  • Operating Pressures05.2 bar, 070 psig
  • Fluid Inventory70 liters (18 gallons)
  • Operating Temperatures10150 degrees C
  • Pump Power: 50 HP
  • Operating Flow Rates0-54 kg/s, (0-850 GPM)
  • Experimental Measurements: flow rates, point temperatures, static pressure, differential pressure

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