Results 221 to 230 of about 14,958 (259)

Nodal diffusion methods for space-time neutron kinetics

Progress in Nuclear Energy, 2007
After recalling the space-time kinetics equations, the finite-element method is presented as a general discretization technique and then applied to the so-called nodal diffusion methods, both primal and mixed-hybrid ones, for the space discretization. In the last section of the paper, a general nodal formalism is applied to the time discretization.
Lawrence M. Grossman, Jean-Pierre Hennart   +1 more
exaly   +2 more sources

Inverse nodal problems for singular diffusion equation

Mathematical Methods in the Applied Sciences
In this study, some properties of the pencils of singular Sturm–Liouville operators are investigated. Firstly, the behaviors of eigenvalues and eigenfunctions is learned, then for each discontinuity point a solution of the inverse problem is given to determine the potential function and parameters , and with the help of a dense set of nodes.
Rauf Amirov, Sevim Durak
exaly   +3 more sources

A Hennart Nodal Method for the Diffusion Equation

Nuclear Science and Engineering, 1995
A modification of the Hennart nodal method for neutron diffusion problems is presented. The final system of equations obtained by this method is not positive definite. However, a flux elimination technique leads to a simple positive definite system, which can be solved by the traditional iterative methods.
P. Lesaint, S. Noceir, D. Verwaerde
openaire   +1 more source

High-Order Analytical Nodal Method for the Multigroup Diffusion Equations

Numerical Algorithms, 2003
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
M. Akhmouch, N. Guessous
openaire   +1 more source

An Adaptive Approach to Variational Nodal Diffusion Problems

Nuclear Science and Engineering, 2001
An adaptive grid method is presented for the solution of neutron diffusion problems in two dimensions. The primal hybrid finite elements employed in the variational nodal method are used to reduce the diffusion equation to a coupled set of elemental response matrices.
Hui Zhang, E. E. Lewis
openaire   +1 more source

Exponential Function Expansion Nodal Diffusion Method

18th International Conference on Nuclear Engineering: Volume 2, 2010
An exponential function expansion nodal diffusion method is proposed to take care of diffusion calculation in unstructured geometry. Transverse integral technique is widely used in nodal method in regular geometry, such as rectangular and hexagonal, while improper in arbitrary triangular geometry because of the mathematical singularity.
Yunzhao Li, Hongchun Wu, Liangzhi Cao, Qichang Chen   +3 more
openaire   +1 more source

A physical interpretation and benchmarking of nodal diffusion error estimators

Annals of Nuclear Energy, 1998
Abstract An error estimator application was evaluated for the analysis and interpretation of nodal solutions of the neutron diffusion problem extended to reactor core level. This error estimator application relies on the residual of the equation and gives a global and local characterisation of approximate solutions by the determination of unbalances ...
F.E. Jatuff, C.J. Gho
openaire   +1 more source

A Fundamental Derivation of the Nodal Diffusion Equation and Its Variation

Nuclear Science and Engineering, 1990
A new nodal interface diffusion equation is derived by applying the second form of Green’s theorem to the transverse-integrated diffusion equation.
Hoju Moon, Samuel H. Levine
openaire   +1 more source

Variational Formulation of a Higher Order Nodal Diffusion Method

Nuclear Science and Engineering, 1990
A higher order nodal diffusion method is formulated, based on variational principle Kantorovich's variational method, and the patch test. In this paper, the relationship between finite element and nodal methods is discussed and the differences are pointed out.
D. V. Altiparmakov, Dj. Tomašević
openaire   +1 more source

Extension of nodal diffusion solver of Ants to hexagonal geometry

Kerntechnik, 2019
Abstract The development of a new computational framework for core multi-physics problems, called Kraken, has been started at VTT Technical Research Centre of Finland Ltd. The framework consists of modular neutronics, thermal hydraulics and thermal mechanics solvers, and is based on the use of continuous-energy Monte Carlo reactor ...
Sahlberg, Ville, Rintala, Antti
openaire   +5 more sources