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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.
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Las Vegas, NV|Mandalay Bay Resort and Casino
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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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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.
Taek Kyum Kim, Chang Hyo Kim
Nuclear Science and Engineering | Volume 123 | Number 3 | July 1996 | Pages 381-391
Technical Paper | doi.org/10.13182/NSE96-A24201
Articles are hosted by Taylor and Francis Online.
A method for determining the mathematical adjoint solution of a higher order nodal expansion method (NEM) based on the simultaneous solution of multigroup equations for each node in the rectangular geometry is presented. In the higher order NEM, the forward NEM equations in a given node include not only the nodal balance and interface-current equations but also weighted residual method (WRM) equations for higher order expansion coefficients. In deriving the mathematical adjoint equations corresponding to these forward NEM equations, the transverse leakage terms in the WRM equations need to be replaced by partial currents. Because transverse leakage terms of a node are linked to partial currents of many neighboring nodes, replacement of transverse leakage terms by partial currents results in complicated WRM equations. Because mathematical adjoint equations are obtained by transposing the nodal forward equations, direct use of these complicated WRM equations makes the numerical computation of the adjoint solution inefficient. This problem is avoided by treating the transverse leakage terms contained in the WRM equations as additional unknowns and by including the equations defining the transverse leakage terms in terms of partial currents into the nodal forward equations. The mathematical adjoint equations are then derived by transposing the resulting nodal forward equations. This adjoint solution method is verified by comparing nodal adjoint fluxes with the fine-mesh VENTURE solution for the International Atomic Energy Agency (IAEA) pressurized water reactor (PWR) benchmark problem and by comparing the local reactivity changes computed with first-order perturbation theory for the IAEA PWR and the Yonggwang unit 2 PWR with the exact reactivity values determined from the eigenvalue difference between perturbed and unperturbed cores.