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Fusion Science and Technology
November 2025
Latest News
Modernizing I&C for operations and maintenance, one phase at a time
The two reactors at Dominion Energy’s Surry plant are among the oldest in the U.S. nuclear fleet. Yet when the plant celebrated its 50th anniversary in 2023, staff could raise a toast to the future. Surry was one of the first plants to file a subsequent license renewal (SLR) application, and in May 2021, it became official: the plant was licensed to operate for a full 80 years, extending its reactors’ lifespans into 2052 and 2053.
Gerald E. Youngblood, David J. Senor, Russell H. Jones
Fusion Science and Technology | Volume 45 | Number 4 | June 2004 | Pages 583-591
Technical Paper | doi.org/10.13182/FST04-A533
Articles are hosted by Taylor and Francis Online.
The hierarchical two-layer (H2L) model describes the effective transverse thermal conductivity (keff) of a two-dimensional (2-D) SiCf /SiC composite plate made from stacked and infiltrated woven fabric layers in terms of constituent properties and microstructural and architectural variables. The H2L model includes the effects of fiber-matrix interfacial conductance, high-fiber packing fractions within individual tows, and the nonuniform nature of 2-D fabric/matrix layers that usually include a significant amount of interlayer porosity. Previously, H2L model keff predictions were compared to measured values for two versions of 2-D Hi-NicalonTM/pyrocarbon (PyC)/isothermal chemical vapor infiltration (ICVI)-SiC composite, one with a "thin" (0.11-m) and the other with a "thick" (1.04-m) PyC fiber coating, and for a 2-D TyrannoTM SA/thin PyC/forced flow chemical vapor infiltration SiC composite. In this study, H2L model keff predictions were compared to measured values for a 2-D SiCf /SiC composite made using the ICVI process with Hi-Nicalon type S fabric and a thin PyC fiber coating. The values of keff determined for the latter composite were significantly greater than the keff values determined for the composites made with either the Hi-Nicalon or the Tyranno SA fabrics. Differences in keff values were expected for the different fiber types, but major differences also were due to observed microstructural and architectural variations between the composite systems, and as predicted by the H2L model.
