ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
Standards Program
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!
Latest Magazine Issues
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
June 2025
Nuclear Technology
Fusion Science and Technology
May 2025
Latest News
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Novak Zuber, F. W. Staub
Nuclear Science and Engineering | Volume 30 | Number 2 | November 1967 | Pages 268-278
Technical Paper | doi.org/10.13182/NSE67-A17337
Articles are hosted by Taylor and Francis Online.
In the past it has been customary to analyze problems concerned with predicting the transient behavior of the concentration in terms of the diffusion equation and, in particular, in terms of Fick's Law. In this paper, the transient behavior of the vapor volumetric concentration in a two-phase flow system with a change of phase is formulated in terms of kinematic waves, and expressed as a propagation equation. The derived void propagation equation predicts the void response to variations of 1) power density, 2) liquid inlet velocity, 3) system pressure, 4) thermodynamic nonequilibrium in the liquid and/or in the vapor, 5) compressibilities of the liquid and of the vapor, 6) flow regime, and 7) body forces. For a boiling forced-flow system, the results of the analysis show that 1) The rate of propagation of the voids, as well as the change, i.e., the distortion of the void disturbance as it propagates along the duct, can be predicted by means of kinematic waves. 2) The rate of propagation of kinematic waves depends on the volumetric flux density of the mixture, the drift velocity of the vapor, and the vapor volumetric concentration. 3) Since the velocity of kinematic waves depends on concentration, the wave forms may develop discontinuities resulting in kinematic shock waves. 4) The void response depends, definitively, upon the flow regime and it may change, completely, with a change in flow pattern.