Computer Programs

NAME OR DESIGNATION OF PROGRAM, COMPUTER, DESCRIPTION OF PROBLEM OR FUNCTION, METHOD OF SOLUTION, RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM, TYPICAL RUNNING TIME, UNUSUAL FEATURES OF THE PROGRAM, RELATED AND AUXILIARY PROGRAMS, STATUS, REFERENCES, MACHINE REQUIREMENTS, LANGUAGE, OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED, OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS, NAME AND ESTABLISHMENT OF AUTHOR, MATERIAL, CATEGORIES

[ top ]

[ top ]

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 |
---|---|---|---|

SWAP-9 | NESC0828/01 | Tested | 18-MAY-1984 |

Machines used:

Package ID | Orig. computer | Test computer |
---|---|---|

NESC0828/01 | CDC CYBER 740 | CDC CYBER 740 |

[ top ]

3. DESCRIPTION OF PROBLEM OR FUNCTION

SWAP9 is a computer program for solving stress-wave problems in one-dimensional strain. It handles both hydrostatic and elastic-plastic materials, can incorporate such effects as work hardening, changes in elastic constants, and yield strength with pressure and internal energy, and spall at a given tensile stress. SWAP9 can also treat detonations, gases, and vapor- ization of solids resulting from radiant energy deposition.

SWAP9 is a computer program for solving stress-wave problems in one-dimensional strain. It handles both hydrostatic and elastic-plastic materials, can incorporate such effects as work hardening, changes in elastic constants, and yield strength with pressure and internal energy, and spall at a given tensile stress. SWAP9 can also treat detonations, gases, and vapor- ization of solids resulting from radiant energy deposition.

[ top ]

4. METHOD OF SOLUTION

SWAP9 uses the method of characteristics approach to the solution of hyperbolic partial differential equations which represents all wave shapes by a series of shock waves. The program is given a set of initial conditions consisting of a mathematical description of all lines existing on the x,t plane plus the equations of state of the materials involved. One line must be specified for each shock, interface, and free-surface. After solving the initial interaction, the program modifies its picture of the x,t plane to fit the new conditions, then solves for the next interaction in the time sequence, etc. The equations for solving the various interactions are derived from the conservation equations for mass, momentum, and energy across an one-dimensional shock front.

SWAP9 uses the method of characteristics approach to the solution of hyperbolic partial differential equations which represents all wave shapes by a series of shock waves. The program is given a set of initial conditions consisting of a mathematical description of all lines existing on the x,t plane plus the equations of state of the materials involved. One line must be specified for each shock, interface, and free-surface. After solving the initial interaction, the program modifies its picture of the x,t plane to fit the new conditions, then solves for the next interaction in the time sequence, etc. The equations for solving the various interactions are derived from the conservation equations for mass, momentum, and energy across an one-dimensional shock front.

[ top ]

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

The basic assumptions about the nature of the problem to be solved are: (a) Only one dimensional motion in rectilinear coordinates is

present, i.e., the components of material velocity in the

lateral direction are zero at all times.

(b) The materials of the problem are strain-rate independent.

(c) The materials obey either hydrodynamic or elastic-plastic

theory, assuming either Von Mises' or Tresca's yield

criterion. These criteria are identical under one

dimensional strain conditions.

A maxima or 25 different materials is allowed with up to 50 constants for each material. The maximum number of lines active on x,t plane at any given time is 300.

The basic assumptions about the nature of the problem to be solved are: (a) Only one dimensional motion in rectilinear coordinates is

present, i.e., the components of material velocity in the

lateral direction are zero at all times.

(b) The materials of the problem are strain-rate independent.

(c) The materials obey either hydrodynamic or elastic-plastic

theory, assuming either Von Mises' or Tresca's yield

criterion. These criteria are identical under one

dimensional strain conditions.

A maxima or 25 different materials is allowed with up to 50 constants for each material. The maximum number of lines active on x,t plane at any given time is 300.

[ top ]

6. TYPICAL RUNNING TIME

The solution time is determined by the number of shock interactions which must be solved to provide the desired information and by the amount of output required. A typical problem can be run at the rate of about 3000 interactions per minute on the CDC600. NESC executed the four sample problems in 50 CP seconds on a CDC7600.

The solution time is determined by the number of shock interactions which must be solved to provide the desired information and by the amount of output required. A typical problem can be run at the rate of about 3000 interactions per minute on the CDC600. NESC executed the four sample problems in 50 CP seconds on a CDC7600.

NESC0828/01

NEA-DB executed the four test cases included in the package on CDC CYBER 740. The following CPU times were required:Test Case CPU seconds

--------- -----------

1 29

2 137

3 96

4 366

[ top ]

[ top ]

[ top ]

10. REFERENCES

L.M. Barker and E.G. Young,

SWAP9: An Improved Stress Wave Analyzing Program,

SLA-74-0009, July 1976.

L.M. Barker,

SWAP7: A Stress-Wave Analyzing Program,

SC-RR-67-143, April 1967.

R.J. Lawrence, D.S. Mason and S.E. Benzley,

Dynamic Material Property Library,

SC-DR-68-885, December 1968.

W. Herrmann, P. Holzhauser, and R.J. Thompson,

WONDY, A Computer Program for Calculating Problems of Motion in

One Dimension,

SC-RR-66-601, February 1967.

L.M. Barker and E.G. Young,

SWAP9: An Improved Stress Wave Analyzing Program,

SLA-74-0009, July 1976.

L.M. Barker,

SWAP7: A Stress-Wave Analyzing Program,

SC-RR-67-143, April 1967.

R.J. Lawrence, D.S. Mason and S.E. Benzley,

Dynamic Material Property Library,

SC-DR-68-885, December 1968.

W. Herrmann, P. Holzhauser, and R.J. Thompson,

WONDY, A Computer Program for Calculating Problems of Motion in

One Dimension,

SC-RR-66-601, February 1967.

[ top ]

NESC0828/01

The test cases were executed on CDC CYBER 740 in 114,200 octal words of main storage.[ top ]

NESC0828/01

NOS 1.4 (CDC CYBER 740).[ top ]

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

NESC

supplied dummy plotting routines EXTFLM, HDCOPY, and PLOTXY, and the RELEASE subroutine to test the SWAP9 package. Subroutine RELEASE returns a tape unit, and the plotting routines are used in conjunction with a SD-4020 film recorder at Sandia Laboratories.

If desired, subroutine XTPLOT may be removed; this will eliminate all references to the plotting routines.

When the available built-in equation-of-state options are not sufficient to describe the material behaviour for a particular problem, the user can write his own subroutines ADSTATE. The SWAP9 package makes use of the CDC UPDATE utility program to modify subroutinE ADSTATE for the second and third sample problems. Users implementing SWAP9 on other computers will have to supply a suitable alternative.

NESC

supplied dummy plotting routines EXTFLM, HDCOPY, and PLOTXY, and the RELEASE subroutine to test the SWAP9 package. Subroutine RELEASE returns a tape unit, and the plotting routines are used in conjunction with a SD-4020 film recorder at Sandia Laboratories.

If desired, subroutine XTPLOT may be removed; this will eliminate all references to the plotting routines.

When the available built-in equation-of-state options are not sufficient to describe the material behaviour for a particular problem, the user can write his own subroutines ADSTATE. The SWAP9 package makes use of the CDC UPDATE utility program to modify subroutinE ADSTATE for the second and third sample problems. Users implementing SWAP9 on other computers will have to supply a suitable alternative.

[ top ]

[ top ]

NESC0828/01

File name | File description | Records |
---|---|---|

NESC0828_01.002 | SWAP-9 INFORMATION | 62 |

NESC0828_01.004 | SWAP-9 SOURCE (COMPILER READY FORM) | 2349 |

NESC0828_01.005 | SWAP-9 INPUT DATA FOR TEST CASE 1 | 15 |

NESC0828_01.006 | SWAP-9 INPUT DATA FOR TEST CASE 2 | 21 |

NESC0828_01.007 | SWAP-9 INPUT DATA FOR TEST CASE 3 | 28 |

NESC0828_01.008 | SWAP-9 INPUT DATA FOR TEST CASE 4 | 17 |

NESC0828_01.009 | SWAP-9 PRINTED OUTPUT OF TEST CASE 1 | 4461 |

NESC0828_01.010 | SWAP-9 PRINTED OUTPUT OF TEST CASE 2 | 2354 |

NESC0828_01.011 | SWAP-9 PRINTED OUTPUT OF TEST CASE 3 | 5396 |

NESC0828_01.012 | SWAP-9 PRINTED OUTPUT OF TEST CASE 4 | 12623 |

NESC0828_01.013 | CONTROL INFORMATION | 79 |

NESC0828_01.014 | LIBRARY GENERATION PROGRAM | 15 |

NESC0828_01.015 | LIBRARY DATA | 204 |

[ top ]

- I. Deformation and Stress Distributions, Structural Analysis and Engineering Design Studies

Keywords: elasticity, hydrodynamics, one-dimensional, plasticity, shock waves, strains, stresses, wave propagation.