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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
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.