SPEC CPU2000 Benchmark Description File

Benchmark Name: 191.fma3d (FMA-3D)

Benchmark Author: Samuel W. Key (swkey@worldnet.att.net)
 For current version and availability information, please contact:
   Samuel W. Key
   dba KEY Associates
   1851 Tramway Terrace Loop NE
   Albuquerque, NM 87122
   USA
  Telephone and Fax: (505) 856-1488
 This information is current as of October 1999.

Benchmark Program General Category:  Mechanical Response Simulation

Benchmark Description:

FMA-3D is a finite element method computer program designed to simulate
the inelastic, transient dynamic response of three-dimensional solids and
structures subjected to impulsively or suddenly applied loads. As an
explicit code, the program is appropriate for problems where high rate
dynamics or stress wave propagation effects are important. In contrast to
programs using implicit time integration algorithms, the program uses a
large number of relatively small time steps, with the solution for the
next configuration of the body being explicit (and inexpensive) at each
step. To further reduce the computational effort, the program has a
complete implementation of Courant subcycling in which each element is
integrated with the maximum time step permitted by local stability
criteria. For simulations that have large differences in element critical
time steps over the mesh, very significant savings in execution time are
achieved. There are no inherent limits on the size of an analysis model,
and storage allocation is dynamic within the code.

The program may be applied to static and quasi-static problems either by
using the dynamic relaxation option or by simply applying the external
loads slowly and integrating the dynamics equations until all significant
transients have died out.

The algorithms and architecture of the program are designed for accuracy
and robustness.  The solution portion of the program is in a form
suitable for cache-based computer hardware architectures. The program is
written in Fortran-90 and consists of over 50,000 lines of code and
comments. The program's key features include:

* Innovative techniques for managing large model databases
* A complete library of finite elements including rigid bodies
* An extensive assortment of constraint and loading options
* Practical sliding interfaces for multi-component analyses
* Extensive options for model modification during a simulation
* Transient dynamic analysis using Courant subcycling
* One-, two- and three-dimensional strain gauges.

Element Library

The program has a large selection of quality finite elements from which
to choose for constructing a model. The element formulations all handle
geometric and material nonlinearities  and do not lock for incompressible
materials.  The element library has formulations that include:

* 8-Node hexahedral continuum elements.
* 6-Node pentahedral continuum elements.
* 4-Node tetrahedral continuum elements.
* 8-Node quadrilateral thick shell elements
* 4-Node quadrilateral shell elements
* 3-Node triangular shell elements
* 4-Node quadrilateral membrane elements
* 3-Node triangular membrane elements
* 2-Node integrated beam elements
* 2-Node truss elements
* 2-Node spring elements
* 2-Node damper elements

Material Modeling

To simulate realistically a variety of material behavior, the program has
a collection of very practical stress-strain models with well established

integration algorithms. The program's library of material models
includes:

* Elasticity and plasticity (isotropic and anisotropic)
* Accurate, smooth hardening plasticity for metal forming
* Incompressible rubber elasticity
* Viscoelasticity
* Volumetric compaction
* Rate dependence

Input Description:

  The SPEC Reference input workload is the simulation of an impulsive
load (initial velocity condition) applied to a cylindrical panel (thin
shell structure supported by clamped, simply supported, and symmetry
boundary conditions). A very fine finite element mesh (a large number of
finite elements) is used to obtain a 100 MB RAM-resident data set for the
simulation.

Output Description:

  Based on the program's ability to provide edited printer output, only
the displacements at two specific nodal points are printed. These two
nodal points are at the edge of the impulsive load where the initial
velocity conditions are discontinuous and, therefore, the response of the
cylindrical panel is initially the most interesting.

Programming Language:  Fortran-90

Known Portability Issues:

  Apart from compiler-specific and machine-specific optimization issues,
the only recommended compiler switch for this version of the program for
general use is -static.

Reference:

 Key, S. W. and C. C. Hoff, "An Improved Constant Membrane and
    Bending Stress Shell Element for Explicit Transient Dynamics," Computer
    Methods in Applied Mechanics and Engineering, Vol. 124, pp 33-47, 1995.