What's New | ||
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R2022x FD01 (FP.2205)
- Newly added diagnostics inform you about large implicit constraint systems in your model.
- Diagnostics are now available to inform you about large implicit constraint
systems in your model that can cause performance degradation. These diagnostic messages
refer to automatically generated node sets associated with such systems. Large implicit
constraint systems are typically associated with overlaps among constraints or overlaps
among constraints and connector element. Solving these large systems of equations in
each increment of Abaqus/Explicit can degrade performance significantly. The sizes of such systems and estimates of the
number of operations required to solve each system are tabulated in the status file. Abaqus/Explicit issues an error message if severe performance degradation is expected. Optionally,
you can change the error message to a warning.
The figure below shows an example of a model with an implicit system of constraint equations associated with the highlighted nodes. This region has redundant surface-based tie specifications with opposite main and secondary surface roles.
The output in the status file informs you about a moderately sized implicit system that has 201 degrees of freedom and would require 140,499 operations to solve during each iteration of the solution. The diagnostic message for this implicit system of equations is informational (rather than a warning or error message) because the number of computational operations to solve the system of equations is moderate. The highlighted nodes are associated with an automatically generated node set referred to by the diagnostic message. The TriggerNodeSet is a set of nodes that most likely have constraints that require implicit solution. In general, studying constraints and connections associated with such node sets might help you understand the source of overlap associated with the implicit system of equations. Avoiding redundant tie specifications enable this simulation to run about 30% faster. Larger speedups can occur for larger implicit systems of constraint equations.
