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.
Explore membership for yourself or for your organization.
Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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
Jul 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
August 2025
Fusion Science and Technology
Latest News
The Frisch-Peierls memorandum: A seminal document of nuclear history
The Manhattan Project is usually considered to have been initiated with Albert Einstein’s letter to President Franklin Roosevelt in October 1939. However, a lesser-known document that was just as impactful on wartime nuclear history was the so-called Frisch-Peierls memorandum. Prepared by two refugee physicists at the University of Birmingham in Britain in early 1940, this manuscript was the first technical description of nuclear weapons and their military, strategic, and ethical implications to reach high-level government officials on either side of the Atlantic. The memorandum triggered the initiation of the British wartime nuclear program, which later merged with the Manhattan Engineer District.
Ronald D. Boyd, Sr.
Fusion Science and Technology | Volume 16 | Number 3 | November 1989 | Pages 324-330
Technical Paper | Blanket Engineering | doi.org/10.13182/FST89-A29124
Articles are hosted by Taylor and Francis Online.
Steady-state subcooled water flow boiling experiments were carried out in a uniformly heated horizontal circular channel with an exit pressure of 1.66 MPa and with the mass velocity G varying from 4.4 to 32.0 Mg/m2·s. The test section, which was made of high-strength zirconium-copper, consisted of a tube with an inside diameter of 0.3 cm and a heated length-to-diameter ratio (L/D) of 96.6. The coolant was degassed and deionized water. The inlet water temperature was held constant at 20°C. These experiments are related to high heat flux removal in fusion reactor beam dumps and first walls in compact fusion reactors. For the chosen values of L/D and exit pressure, the measured critical heat flux (CHF) values are higher than any previous values for smooth tubes in the literature. The effect of increasing the pressure from 0.77 to 1.66 MPa is to increase the CHF progressively from 2.0 to 19% as the mass velocity is increased from 4.4 to 25.0 Mg/m2·s. The percent increase in the CHF dropped to 10.0% as G increased from 25.0 to 32.0 Mg/m2·s. Below 25.0 Mg/m2·s, the relationship between the CHF and the mass velocity is linear. Further, an increase in the exit pressure resulted in an increase in the slope of this relationship. However, the local heat transfer coefficient actually decreased as the pressure increased, for the same power level and mass velocity.