Parameter

Values

Description

APPROX

< FULL or REDUCED >

Default = FULL

Approximation type switch for stress/strain responses for shells, composites and 1D elements.

When REDUCED is chosen, some stress/strain responses will use the constant force approximation. This method has the benefit of reducing the memory requirement for large optimization problems (many stress/strain responses for many size design variables). Another benefit is the reduction in runtime if the bottleneck occurs due to sensitivity analysis. It is encouraged to try the REDUCED option for the large size optimization model, and, if the FULL option results in the error 832 (Optimization problem is too big to be solved by OptiStruct).