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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
Meeting Spotlight
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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Latest News
Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
Hyun Chul Lee, Chang Hyo Kim
Nuclear Science and Engineering | Volume 138 | Number 2 | June 2001 | Pages 192-204
Technical Paper | doi.org/10.13182/NSE01-A2209
Articles are hosted by Taylor and Francis Online.
This paper demonstrates that the analytic nodal method (ANM) solution to two-group (2-G) diffusion equations can be formulated in the same way as the nodal expansion method (NEM) solution, and thereby, the two most popular transverse integrated nodal method formulations can be integrated into a unified nodal method (UNM) formulation. For this purpose, the analytic solution, i.e., the combined homogeneous and particular solution, of transverse-integrated one-dimensional, 2-G diffusion equations is represented by an expansion of analytic basis functions while the expansion coefficients are obtained in the same way as the NEM. The advantages of the UNM formulation are then discussed. It is a stable method in itself so that it does not require approximate schemes to avoid the instability at the near-critical nodes. Because it does not introduce any approximate scheme in conjunction with the stability questions at the near-critical nodes, it is more accurate than the conventional ANM formulation in the case where the latter needs to introduce approximations. It is readily incorporated into a number of existing NEM production codes. These advantages are demonstrated in terms of numerical solutions of Nuclear Energy Agency Committee on Reactor Physics pressurized water reactor benchmark problems.