NEA-0443 FEM-2D. (Abstract last modified 01-JUL-1978)
1.
NAME OR DESIGNATION OF PROGRAM - FEM-2D. 2.
COMPUTER FOR WHICH PROGRAM IS DESIGNED AND OTHER MACHINE VERSION PACKAGES AVAILABLE -
To request or retrieve programs click on the one of the active versions below.
A password and special authorization is required. Explanation of the status codes.
Machines used:
Package-ID Orig.Computer Test Computer
NEA-0443/01 CDC CYBER 173 CDC CYBER 173
3.
NATURE OF PHYSICAL PROBLEM SOLVED - FEM-2D solves the two-dimensional diffusion equation in x-y geometry. This is done by the finite elements method. 4.
METHOD OF SOLUTION - FEM-2D uses triangular elements with first and second order Lagrange approximations. The systems equations are formulated in multigroup form and solved by Cholesky procedure which operates only on nonzero elements. Various acceleration techniques are available for the outer iteration. Fluxes along various lines and rates in arbitrary zones may be output. 5.
RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM - The code uses variable dimensioning. Thus, the problem size is restricted by the largest array which usually is the systems matrix. Fluxes of all groups are kept in memory. This might become another restrictive data set for a large number of groups. The validity of the results is restricted by the approximations used. FEM-2D requires a finite element net which allows the approximation of fluxes by at most parabolas. The node distribution should be more dense in areas of heavy flux changes (near absorbers or the reflector). 6.
TYPICAL RUNNING TIME - The running time is determined by the number of elements, the number of nodes and the approximation used. Due to the source and rate calculations, the number of nodes is the least important factor. Typical running times on a CDC 6600 for a two group problem are - 7.
UNUSUAL FEATURES OF THE PROGRAM - 8.
RELATED AND AUXILIARY PROGRAMS - RSIMK simulates parts of the RSYST modular system. 9.
STATUS 10.
REFERENCES - 11.
MACHINE REQUIREMENTS - CDC 6600 - use of disks for multigroup problems. Use of extended core storage for BLOCK DATA. 12.
PROGRAMMING LANGUAGE(S) USED - 13.
OPERATING SYSTEM OR MONITOR UNDER WHICH PROGRAM IS EXECUTED - SCOPE. 14.
ANY OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS - FEM-2D is written in overlay mode. 15.
NAME AND ESTABLISHMENT OF AUTHOR - 16.
MATERIAL AVAILABLE - 17.
CATEGORIES - Keywords: DIFFUSION EQUATIONS, FINITE ELEMENT METHOD, LAGRANGE EQUATIONS, POWER REACTORS, TWO-DIMENSIONAL, X-Y
Program-name Package-ID Status
FEM-2D NEA-0443/01 Tested
------------------------------------------------------
nodes elements approximation time/iteration (sec)
------------------------------------------------------
177 301 first order 0.26
654 1204 first order 0.70
501 228 second order 0.48
654 301 second order 0.61
746 345 second order 0.70
NEA-0443/01: 01-JUL-1978 Tested at NEADB
NEA-0443/01:
- H.P. Franke and F.A.R. Schmidt:
FEM2D - Program for Solving the Two-Dimensional Diffusion Equation by the
Method of Finite Elements
Progress Report of Research Task RB 78 I
July 1, 1974, Report Number 4-25 (ORNL-tr-2971)
- F.A.R. Schmidt and H.P. Franke:
Power Reactor Calculation with the Finite Elemen Program FEM 2D
Technical Notes (Reprint from Nucl. Sci. & Eng. 56, 431-433
- F.A.R. Schmidt:
FEM-2D - Input Description and Performance
March 1975, ike 4-43
NEA-0443/01: FORTRAN-IV
It uses the following COMPASS routines -
VEKMSKA - multiplies a vector by a SCALAR
VEKMVEK - multiplies a vector by a vector.
UTYLITY - transfers data array to the disk without using a buffer area.
Institut fuer Kernenergetik
University of Stuttgart
7000 Stuttgart 80
Pfaffenwaldring 31
Germany, F.R.
NEA-0443/01:
NEA0443_01.001 INFORMATION 5 records
NEA0443_01.002 'RSIMK' - SOURCE PROGRAM (F4+COMPASS) 539 records
NEA0443_01.003 SOURCE PROGRAM (F4,COMPASS) 4987 records
NEA0443_01.004 SAMPLE PROBLEM INPUT DATA 62 records
NEA0443_01.005 SAMPLE PROBLEM PRINTED OUTPUT 490 records
- C. Static Design Studies
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