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Access anywhere, anytime: Nuclear power, Ice Camp, and Rickover’s enduring standard of excellence
Admiral William Houston
As U.S. Navy submarines surface through Arctic ice during Ice Camp 2026, they demonstrate more than operational proficiency in one of the harshest environments on Earth. They reaffirm a technological truth first proven in August 1958, when the USS Nautilus completed its submerged transit of the North Pole: nuclear power enables access anywhere, anytime.
The Arctic is unforgiving, with vast distances, extreme cold, shifting ice, and no logistical infrastructure. Conventional propulsion is constrained by fuel, air, and endurance. Nuclear propulsion removes those constraints. Only a nuclear-powered submarine can operate anywhere in the world’s oceans, including under the polar ice, undetected and at maximum capability for extended periods. Nuclear power provides sustained high speed and the endurance to reposition across the globe without refueling.
Rafael Macian, Paul Coddington
Nuclear Technology | Volume 139 | Number 3 | September 2002 | Pages 185-204
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT02-A3313
Articles are hosted by Taylor and Francis Online.
RETRAN-3D, a system analysis code currently employed by the nuclear industry in studies covering a wide variety of operational and accident scenarios, has not been extensively validated for application to loss-of-coolant accident (LOCA) scenarios.The results of the in-depth analysis of two experimental loss-of-coolant transients, namely, Test No. 9 in the French OMEGA facility, and the International Standard Problem 26 (ISP-26) in the Japanese ROSA-IV Facility are discussed. The OMEGA test simulated the blowdown phase of a double-ended cold-leg break, whereas the ISP-26 test simulated a small break (5%) in a full height, volume (1/48), and power (~1/342) scaled facility representing a typical two (or four)-loop pressurized water reactor (PWR) system.The RETRAN-3D results for the OMEGA test show good estimates of the important system parameters, with the best agreement corresponding to the use of the dynamic-slip flow model. A sensitivity analysis on the break flow showed that the Henry/Fauske-Isoenthalpic Expansion critical flow model yields the best results, which are significantly improved with a refined nodalization upstream of the break.The ISP-26 was also simulated using the dynamic-slip flow model. The results indicate that the code is able to calculate a small-break LOCA with a model including the main PWR system components and to reproduce the principal physical processes in a reasonable manner.In summary, this assessment shows the ability of RETRAN-3D to model LOCA scenarios in a reasonable way and also points to areas where further model improvement could result in more accurate simulations.
