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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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Proving DRACO will deliver
The United States is now closer than it has been in over five decades to launching the first nuclear thermal rocket into space, thanks to DRACO—the Demonstration Rocket for Agile Cislunar Orbit.
Dmitry V. Paramonov, Mohamed S. El-Genk
Nuclear Technology | Volume 117 | Number 1 | January 1997 | Pages 1-14
Technical Paper | Fission Reactor | doi.org/10.13182/NT97-A35332
Articles are hosted by Taylor and Francis Online.
The Soviet-made TOPAZ-II space nuclear power system unit designated Ya-21u underwent a total of 15 tests both in the Union of Soviet Socialist Republic (USSR) (1989–1990) and in the United States (August 1993 to March 1995) for a cumulative test/operation time of 7681 h at conditions far exceeding design limits. These tests included steady-state operation at different power levels, fast start-ups and power optimizations, and shock and vibration tests. Test results are presented and analyzed. Results indicate a gradual change in the performance parameters such as the optimum cesium pressure and optimum load voltage. The electric power and conversion efficiency of the unit at an input thermal power of 105 kW decreased from 3.7 kW(electric) and 4% in the test in the USSR to 2.13 kW(electric) and 2.3 % in the last test in the United States. A discussion and qualitative assessment of potential causes of the performance changes of the Ya-21u unit are given.