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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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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!
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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.
Ronald D. Boyd
Fusion Science and Technology | Volume 13 | Number 4 | May 1988 | Pages 644-653
Technical Paper | Blanket Engineering | doi.org/10.13182/FST88-A25139
Articles are hosted by Taylor and Francis Online.
A quasi-automated high heat flux flow boiling facility has been developed for the systematic study of critical heat flux (CHF), heat transfer, and two-phase pressure drop. High heat flux research is important in state-of-the-art electronics and fusion component design. For fusion applications, there are practically no low-pressure data for large values of coolant channel length-to-diameter (L/D) ratio (i.e., 100), channel diameters near 1.0 cm, and medium to high heat flux levels (i.e., 100 to 2000 W/cm2). A second step is provided to fill this void. Forced flow boiling (with water) quasi-steady experiments have been conducted on uniformly (resistively) heated horizontal copper tubes. The tubes were 1.02 cm in inside diameter and 117.87 cm long. The inlet water temperature was 20°C. For a 1.6-MPa exit pressure, measurements of the CHF varied from the annular flow regime (150 W/cm2) to the subcooled flow boiling regime (425 W/cm2). The mass velocity was varied from 0.63 to 3.5 Mg/m2·s. At 1.6 MPa, the transition between the annular and subcooled CHF regimes was measured to occur between 1.03 and 1.26 Mg/m2·s. Large axial variations in the Nusselt number were also measured. For example, at 1.7 Mg/m2·s, the Nusselt number varied from 120 at the channel's entrance to 500 at the exit. The CHF data were compared with correlations developed by Bowring, Katto, and Merilo. Below 4.0 Mg/m2, all correlations overpredicted the CHF data. Merilo's correlation, which was developed for high-pressure horizontal flows, predicted the CHF significantly above the present low-pressure data. The effects of orientation on the CHF data were small. Visual observations of the outside of the test section showed that burnout occurred simultaneously around the test section's perimeter. Circumferential measurements of the outside wall temperature also showed negligible variations. Therefore, at low pressures, the following conditions reduced the effect of orientation: 1. high liquid Reynolds number 2. high inlet subcooling 3. moderate L/D 4. increased effects of surface tension relative to buoyant and viscous forces at higher pressures (i.e., low Bond and Ohnesorge numbers)5. low value of buoyant forces relative to inertia forces.
