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BWXT starts building Pele microreactor core
Fabrication of the reactor core for the 1.5-MW Project Pele demonstration microreactor has begun, according to BWX Technologies. Pele is being developed at the BWXT Innovation Campus in Lynchburg, Va., for the U.S. Department of Defense’s Strategic Capabilities Office.
D. Squarer, L. E. Hochreiter, A. T. Pieczynski
Nuclear Technology | Volume 65 | Number 1 | April 1984 | Pages 16-22
Technical Paper | Postaccident Debris Cooling / Heat Transfer and Fluid Flow | doi.org/10.13182/NT84-A33368
Articles are hosted by Taylor and Francis Online.
In the worst hypothetical accident in a light water reactor, when all protection systems fail, the core could be converted into a deep particulate bed either in-vessel or ex-vessel. The containment of such an accident depends on the coolability of a heat-generating debris bed. Some recent experimental and analytical studies that are concerned with heat removal from such a particulate bed are reviewed. Studies have indicated that bed dryout flux and, therefore, the heat removal rate from the particulate bed increases with the particle diameter (i.e., the permeability) for pool boiling conditions and can exceed the critical heat flux of a flat plate. Bed dryout in a large particle bed (i.e., a few millimetres) was found to be closely related to the “flooding” limit of the bed. Dryout under forced flow conditions was found to be affected by both forced and natural convection for mass flow rate smaller than whereas above this mass flow rate, bed dryout is proportional to the mass flow rate. Recent analyses were found to be in agreement with experimental data; however, additional research is needed to assess factors not accounted for in previous studies (e.g., effect of pressure, multidimensionality, stratification, etc.). Based on the expected pressure and particle sizes in a postulated severe accident sequence, a debris bed should be coolable, given a sufficient water supply.