S-Space College of Engineering/Engineering Practice School (공과대학/대학원) Dept. of Energy Systems Engineering (에너지시스템공학부) Nuclear Engineering (원자핵공학전공) Journal Papers (저널논문_원자핵공학과)
Stabilization techniques for the nonlinear analytic nodal method
- Joo, Han Gyu; Jiang, Guibing; Downar, Thomas J.
- Issue Date
- American Nuclear Society
- Nucl. Sci. Eng., 130, 47 (1998)
- The nonlinear analytic nodal method, which is formulated by combining the nonlinear iteration technique and the analytic nodal method (ANM). requires analytic solutions of the two-node problems. When the method is applied to problems that contain near-critical nodes in which there is essentially no net leakage, the two-node ANM solution for such nodes result in highly ill-conditioned matrices and potential numerical instabilities, especially in single precision arithmetic. Two stabilization techniques are introduced to resolve the instability problem by employing alternate basis functions for near-critical nudes. The first uses the exact ANM solution for a critical node, and the second employs the nodal expansion method. Both techniques are shown to perform well; however, the solution accuracy can be mildly sensitive to the criterion used to invoke the stabilized coupling kernel.