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Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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February 2025
Latest News
WEST claims latest plasma confinement record
The French magnetic confinement fusion tokamak known as WEST maintained a plasma in February for more than 22 minutes—1,337 seconds, to be precise—and “smashed” the previous record plasma duration for a tokamak with a 25 percent improvement, according to the CEA, which operates the machine. The previous 1,006-second record was set by China’s EAST just a few weeks prior. Records are made to be broken, but this rapid progress illustrates a collective, global increase in plasma confinement expertise, aided by tungsten in key components.
Michael R. Prisco, Robert E. Henry, Michael N. Hutcherson, John L. Linehan
Nuclear Science and Engineering | Volume 63 | Number 4 | August 1977 | Pages 365-375
Technical Paper | doi.org/10.13182/NSE77-A27054
Articles are hosted by Taylor and Francis Online.
Two-phase, critical flow data are reported for initially saturated and subcooled liquid Freon-11 flowing through sharp-edged entrance tubes for length-to-diameter (L/D) ratios from 2.82 to 100. Comparisons among various analytical models and these data show that nonequilibrium models describe the critical flow phenomenon more accurately than equilibrium models. It is shown that to obtain reliable exit plane pressure measurements, it is necessary to have a gradual divergence at the exit of the constant-area tube. This minimizes the expansion of the exiting fluid, which would otherwise result in an exit pressure measurement much lower than the one-dimensional value governing the flow. Utilizing data from this study, quantitative estimates of the individual phase velocities at the condition of critical flow indicate that “vapor choking” is not the mechanism by which two-phase critical flow occurs in this investigation. The flow pattern in a transparent test section, with an L/D ratio of 2.82, has been observed and photographed, and this shows that the separated flow condition (liquid jet surrounded by vapor) begins to break up into a dispersed two-phase mixture approximately one equivalent diameter downstream of the entrance.