Computer Programs
NESC0775 HEMP
last modified: 01-OCT-1980 | catalog | categories | new | search |

NESC0775 HEMP

HEMP, 2-D Elastic Plastic Flow in 2-D X-Y or Cylindrical Geometry by Lagrangian Method

top ]
1. NAME OR DESIGNATION OF PROGRAM:  HEMP
top ]
2. COMPUTERS

To submit a request, click below on the link of the version you wish to order. Rules for end-users are available here.

Program name Package id Status Status date
HEMP NESC0775/01 Tested 01-OCT-1980

Machines used:

Package ID Orig. computer Test computer
NESC0775/01 CDC 7600 CDC 7600
top ]
3. DESCRIPTION OF PROBLEM OR FUNCTION

The  HEMP  code   solves  the
conservation equations of two-dimensional elastic-plastic flow, in
plane x-y coordinates  or in  cylindrical symmetry  around the  x-
axis.   Provisions  for  calculation  of  fixed  boundaries,  free
surfaces, pistons, and  boundary slide planes have  been included,
along with other special conditions.
top ]
4. METHOD OF SOLUTION

The  solution  is  by the  method  of  finite
differences and  uses the  Lagrangian formulation.   The materials
within a physical  system are divided into  quadrilaterals bounded
by J  and K  grid lines.  A  decoupling of  grid lines  is allowed
along K-lines, and voids may open and close between K-lines.
top ]
5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

The maximum number
of J's  in any  K-line is 101.   A problem of  up to  about 10,000
zones may be run.
top ]
6. TYPICAL RUNNING TIME

Basic  HEMP calculation  speed  is about  5
points (or zones)  per millisecond.  The number  of problem cycles
necessary depends on  the problem termination  time and  the time-
step size.   Typical problems  run from a  few minutes  to several
hours with time a function of  zone size, material composition and
activity in the zones.
top ]
7. UNUSUAL FEATURES OF THE PROGRAM

The input  system, described  in
the HEMP  User's Manual is  designed so  that the least  amount of
data to  describe a particular  physical system need  be supplied.
However,  provision  is  made for  describing  initial  conditions
(zonal or nodal) in great detail, if required.
top ]
8. RELATED AND AUXILIARY PROGRAMS:
top ]
9. STATUS
Package ID Status date Status
NESC0775/01 01-OCT-1980 Tested at NEADB
top ]
10. REFERENCES

- Mark L. Wilkins:
  Calculation of Elastic Plastic Flow
  UCRL-7322 Rev. 1 (January 24, 1969).
NESC0775/01, included references:
- E.D. Giroux:
  HEMP User's Manual
  UCRL-51079 Rev. 1 (December 17, 1973).
top ]
11. MACHINE REQUIREMENTS

The  HEMP main  code fills  the small  core
memory (SCM) with  the code, working storage,  library, and system
routines.  The large  core memory (LCM) utilized is  a function of
problem size, the amount required is 527,270 (octal) words.
top ]
12. PROGRAMMING LANGUAGE(S) USED
Package ID Computer language
NESC0775/01 FORTRAN-IV
top ]
13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED:  SCOPE 2.1.
top ]
14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

Memory must be  precleared to zero.  The program treats  LCM as an
input-output storage device.  Data is accessed  to and from LCM in
K-line groups.  The dimensions of variables in LCM numbered COMMON
blocks must be adjusted for each problem.
top ]
15. NAME AND ESTABLISHMENT OF AUTHORS

                 M. L. Wilkins and J. A. Levatin
                 Lawrence Livermore Laboratory
                 P. O. Box 808
                 Livermore, California  94550
top ]
16. MATERIAL AVAILABLE
NESC0775/01
File name File description Records
NESC0775_01.001 SOURCE 14240
NESC0775_01.002 PROBLEM INPUT 29
NESC0775_01.003 PROBLEM OUTPUT 3297
NESC0775_01.004 JCL 13
top ]
17. CATEGORIES
  • I. Deformation and Stress Distributions, Structural Analysis and Engineering Design Studies

Keywords: Lagrange equations, Navier-Stokes equation, elasticity, equations of state, finite difference method, fluid mechanics, hydrodynamics, plasticity, two-dimensional.