Direct solution of the mathematical adjoint equations for an interface current nodal formulation

Conference · Mon Mar 01 00:00:00 EST 1993

OSTI ID:10147053

Taiwo, T A; Yang, W S; Khalil, H S

A numerical method for directly computing the mathematical adjoint flux moments and partial currents for the hexagonal-Z geometry interface current nodal formulation in the DIF3D code is described. The new scheme is developed as an alternative to an existing scheme that employs a similarity transformation of the physical adjoint solution to compute the mathematical adjoint. Whereas the existing scheme is rigorous only when the flat transverse-leakage approximation is employed, this new scheme is exact for all leakage approximations in the DIF3D nodal method. in the new scheme, adjoint nodal equations whose form is very similar to that of the forward nodal equations are derived by employing linear combinations of the adjoint partial currents as computational unknowns in the adjoint equations. This enables the use of the forward solution algorithm with only minor modifications for solving the mathematical adjoint equations. By using the new scheme as a reference method, it is shown numerically that while the results computed with the existing scheme are approximate, they are sufficiently accurate for calculations of global and local reactivity changes resulting from coolant voiding in a liquid metal reactor.

• Research Organization: Argonne National Lab., IL (United States). Reactor Analysis Div.
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 10147053
• Report Number(s): ANL/RA/CP-76759; CONF-930404-10; ON: DE93009961
• Resource Relation: Conference: International topical meeting on mathematical methods and supercomputing in nuclear applications (M&C+SNA `93),Karlsruhe (Germany),19-23 Apr 1993; Other Information: PBD: [1993]
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
22 GENERAL STUDIES OF NUCLEAR REACTORS
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
NEUTRON DIFFUSION EQUATION
NODAL EXPANSION METHOD
NUMERICAL SOLUTION
CROSS SECTIONS
ALGORITHMS
MULTIGROUP THEORY
MATRICES
663610
220100
990200
NEUTRON PHYSICS
THEORY AND CALCULATION
MATHEMATICS AND COMPUTERS