What’s new in Altair OptiStruct 2022?
Continuing to build on more than 25 years of innovation, Altair OptiStruct™ is used globally by industry-leading companies to drive design with optimization and validate structural performance.
The latest release of Altair OptiStruct™ - Altair's optimization-enabled structural analysis tool - now offers extensive capabilities for rate-dependent plasticity analysis and pressure penetration analysis support for nonlinear implicit analysis. It also continues to add significant enhancements in Explicit analysis, such as adaptive dynamic relaxation and improved contact robustness. It additionally includes significant Fatigue analysis enhancements, along with continued improvements to optimization.
OptiStruct in a Nutshell
OptiStruct solves both linear and nonlinear problems across static and dynamic, vibrations, acoustics, fatigue, heat transfer, and Multiphysics disciplines. With its topology optimization driving lightweight, structurally efficient product design today, OptiStruct also offers many other structural optimization methods, along with a broad range of essential manufacturing constraints for traditional processes, composites, and additive manufacturing.
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In this post, we will focus on some of the enhancements in OptiStruct 2022.
Nonlinear Implicit Analysis
Nonlinear Implicit analysis features continue to be aggressively improved in OptiStruct. A few new nonlinear implicit analysis features in OptiStruct 2022 are:
Pressure Penetration
Pressure Penetration interaction can simulate fluid penetrating through the surfaces on a contact interface.
This capability is helpful in simulating applications where the contact interface between two parts (for example threaded bolts) have fluid pressure on either or both ends.
The reference magnitude of the fluid pressure can be defined by you. This feature supports large displacement nonlinear analysis.
Rate-dependent Plasticity
In addition to the previously supported rate-independent plasticity, starting from OptiStruct 2022, you can define the Stress-strain data as:
- Strain-rate dependent Stress-Strain curve
- Temperature-dependent Stress-Strain curve
The columns on the TABLEMD entry can be used to define corresponding strain-rate dependency or temperature-dependency.
Explicit Dynamic Analysis
Significant improvements and enhancements are made to Explicit Dynamic Analysis in OptiStruct to provide you with the most cutting-edge technology for various applications. A couple of new features added in OptiStruct 2022 are:
Adaptive Dynamic Relaxation
Dynamic relaxation can be used to solve static or quasi-static problems using Explicit Dynamic Analysis by avoiding dynamic oscillations. Compared to implicit analysis, it can be more efficient and robust in certain cases with high nonlinearities (for instance, cases with many complicated contacts).
Typical applications include 3-point bending simulations of phone structures and spring back simulation in sheet metal forming.
A key differentiator with dynamic relaxation in OptiStruct is that you can also specify dynamic relaxation without any input parameters. The damping factor is automatically determined based on the system’s highest natural frequency.
As seen in the example above, the Explicit subcase 2 approaches a static solution similar to implicit analysis.
Contact Robustness Enhancement
Contact robustness for explicit analysis is improved for each release, and this continues with OptiStruct 2022.
When the main side of a contact interface is made up of shell elements, a new DRILL option is available for TIE and FREEZE contact. This will allow transmission of moments applied on secondary side of the contact interface to the main side as forces so that the drilling moments are transmitted.
By default:
Using new DRILL option:
Fatigue Analysis
OptiStruct 2022 continues enhancements for Fatigue Analysis by introducing the capability to calculate fatigue damage at solder joints based on nonlinear creep analysis.
Fatigue Damage due to Creep deformation of a Solder joint
Fatigue damage due to creep deformation of solder joints is now supported starting from OptiStruct 2022. The approach assumes that Solder joint failure is caused by creep deformation of solder joints. Damage of the solder joints can be calculated based on:
- Damage calculation using creep strain
- Damage calculation using creep strain energy density.
Both BGA and Leadless solder joints are supported for damage calculation due to creep deformation of the solder joint.
For Damage calculation using Creep strain, the method proposed by Syed is used (SYEDEPS) and for the Damage calculation using Creep strain energy density, the methods proposed by Syed (SYEDW) and Darveaux (DARV) are available.
Optimization
Altair OptiStruct™ is used globally by industry-leading companies to drive design with optimization and validate structural performance. Enhancements to optimization solutions are implemented for each release and similarly, in OptiStruct 2022 many optimization enhancements are available to you, including the following:
Axisymmetric Structural Optimization
Optimization is now supported on axisymmetric models for Shape, Free-shape, and Sizing design variables.
Various responses such as Displacement, compliance, eigenvalue, and Stress are supported.
Augmented Lagrange Method (ALM)
ALM is now available in OptiStruct 2022 to handle local stress constraints for Topology optimization. It is an alternative method to the default P-norm approach.
The following image shows a comparison of final designs between ALM and P-norm methods.
ALM penalizes the stress constraints on to the objective function. Therefore, the total number of stress constraints are reduced significantly, and this leads to an efficient solution. When compared to the P-norm method, the solution using ALM proceeds within a single phase, leading to faster convergence for ALM.
View release notes and download from Altair One: https://altairone.com/Marketplace?queryText=optistruct.