Results post processing

1.3 Result Definitions
CHAPTER 1
Introduction to Results Postprocessing
In order to fully utilize the power of the postprocessor, a thorough understanding of how the
results are stored and manipulated is important. To avoid confusion or the possibility of
misinterpreting the graphical displays, the following definitions should be understood.
Result Types. There are really only three results types, either scalar, vector, or tensor. Aside
from these there are other aspects of results data as stored in the database that need to be
understood. The following table summarizes these:
Term Description
Nodes/Elements Results are associated with either nodes or with elements.
Scalar Results
Vector Results
Tensor Results
Real/Complex
Number
Load Case
Results Case
Single results values associated with either nodes or elements. They
contain a magnitude only with no direction. Examples: strain energy,
temperature, von Mises stress, etc.
Results values with three (3) components each associated with either
nodes or elements. Vector results contain both magnitude and
direction Examples: displacement, velocity, acceleration, reaction
forces, etc.
Results values with six (6) components each (typically comprising
the upper triangular portion of a symmetric matrix) associated with
either nodes or elements. Examples: stress and strain components
Results stored as real numbers have only single values associated
with any node or element. Complex numbers have two values
associated with any node or element and are stored in the database
as real and imaginary parts or magnitude and phase.
A group of applied loads and boundary conditions which may
produce one or more result cases.
A collection of results as stored in the database (e.g., static analysis
results, results from a load step in a nonlinear analysis, a mode shape
from a normal mode analysis, a time step from a transient analysis,
etc.).
Result Type Either scalar, vector, or tensor. Scalar results contain a magnitude
with no direction such as temperature, strain energy, von Mises
stress, etc. Vector results contain both magnitude and direction, such
as displacement, velocity, and acceleration. Tensor results are
symmetric with six unique values (xx, yy, zz, xy, yz, zx) such as stress
or strain at a point. Each Results Case can have many Results types in
them.
Global Variables
Values associated with results cases as a whole rather than to
individual nodes and elements. Each result case may be associated
with zero, one or more global variables, (e.g. time, frequency, load
case, etc.).
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