Altair Manufacturing Solver 2022 Release Notes
General
Altair Manufacturing Solver is a state-of-the-art solver suite for manufacturing
applications built on a parallel, modular, and extensible framework suitable for
simulations of manufacturing processes. This release contains solutions for the
following modules:
- Additive Manufacturing
- Injection Molding (3D Solution)
- Metal Casting
- Welding
- Polymer Material Data Analytics (PMDA)
Highlights
Highlights for this release include:
- The additive manufacturing module improves the robustness and performance of the solver while adding calibration, multi-layer simulation, and automatic rest boundary conditions in springback.
- Polymer Material Data Analytics (PMDA) is a new Python package added in this release to support the injection molding solution. It is used to analyze, validate, and create reports for injection molding materials. This package will be used by the injection molding interfaces in SimLab and Inspire.
Additive Manufacturing (3DP for SLM)
New Features
- Calibration of Inherent Strain Tensor
- A calibration tool is added to determine the correct inherent strain value based on the defined printing conditions. To use this tool, you should print the cantilever specimen defined by the solver and provided by the Inspire interface. To calibrate the inherent strain tensor for a desired 3DP part, the cantilever specimen should be printed with the same material and conditions. Then, using the measured deflection after the springback, the solver calibrates the inherent strain tensor. This calibrated value, when used in simulation, greatly improves the accuracy of the analysis.
- Multi-layer Element
- A 3DP solution often uses an order of magnitude coarser element layer than the actual thickness of the printed layer. This introduces inaccuracies in the simulation. An advanced algorithm has been implemented to improve the numerical solution when simulating by activating several printed layers together as a single element layer. This technology enhances the given inherent strain considering the number of printing layers per element thickness. It significantly lowers the computational cost but without compromising on accuracy.
- Automatic Boundary Condition for Springback Computation
- The deformation and stresses computed often strongly depend on how the part was constrained to eliminate the rotational degrees of freedom and capture only the deformation. The solver now automatically imposes this minimal constraint on the printed part and eliminates the uncertainties/variations from manually constraining the part. This produces more consistent results and removes the need for user specification.
Enhancements
- Improvements to Solver Interface
- The solver parameters are fine-tuned to increase the global performance of the solver.
- Support for Printable Overhanging Regions
- In the previous version, any hanging region would cause the solver to crash. The previous solver assumed a hanging region is not printable. However, there are cases in which small hanging regions can be supported by the powder and printed. In this version, the solver detects and applies special boundary conditions to those overhanging elements and enables the simulation of such parts.
- Automatic Cleanup of Ill-connected Elements
- The solver automatically cleans up the isolated elements and elements that are only connected by the corner nodes or edges (without proper face support). These errors can happen due to the large voxel size compared to the feature size in the model. This correction is applied only in the printing stage of the simulation.
Known Issues
The following are known issues and will be addressed in a future release as we
continuously improve the performance of the software:
- Diagonally connected voxels are not supported in springback: When the voxel size is very coarse, it may create elements that are only connected by corner nodes. This introduces errors, and refining the mesh can overcome this issue.
Metal Casting
New Features
- New Results for Solidification Analysis
- The following nodal results are added for the solidification analysis.
(AMSLVR-316)
- Cooling rate: Shows how fast a node is cooling (temperature variation over time) and is plotted for every time step during the cooling stage.
- Solidification rate: Shows the average cooling rate during solidification (only when the temperature is between liquidus and solidus temperatures). This is plotted only in the last time step.
- Critical cooling rate: Cooling rate at the moment when the node becomes completely solid. It is plotted only at the last time step.
- Mold Erosion
- A new feature to compute mold erosion near the mold surface in contact with the part is implemented. This is a function of the velocity and the residence time. This nodal result is written for the filling stage. (AMSLVR-344)
- Contribution to Filling from Different Inlets
- A new feature to identify from which gate a given region was filled is implemented. Each inlet gate is given an ID and this result is shown as a nodal contour of the inlet IDs. (AMSLVR-197)
- Cooling Calculations after Shake-out
- A new solution stage is implemented to continue the cooling computations after the part shake-out. With this feature, you can continue the cooling analysis of the part after it is taken out of the mold. (AMSLVR-269)
Enhancements
- Handling Solidified Regions During Filling
- The robustness of the filling simulation is improved by setting the velocity in the regions that no longer move to zero. This improves the numerical stability of the solution. (AMSLVR-325)
- Improved Robustness in Flow Length Computation
- Flow length computations determine how long the particle traveled to reach the current nodal position at that time step. This result gives valuable insight into how the part is filled. In this release, the solver has improved the stability of these flow length calculations. (AMSLVR-342)
- User-specified Solidification Time
- In solidification analysis, you can specify the solidification end time. When this is specified, the solver adjusts the time steps to honor the specified end time. (AMSLVR-345)
- Improvements to Convergence of Thermomechanical Simulation
- Thermomechanical simulation is fine-tuned; several improvements have been made to improve the convergence and make the solution robust. (AMSLVR-379)
Resolved Issues
- Temperature of Last Filled Nodes
- The temperature of the nodes that were filled in the last time step was not shown correctly in the previous release. This issue is resolved and the solver correctly extrapolates the temperature of these nodes from the previously filled nodes. (AMSLVR-306)
- Tilt Pouring was Not Working Correctly with Cycling
- Rotation of the model during tilt pouring was not done correctly after the cycling stages. This was due to an error in the handling of simulation time inside the solver. This issue is resolved. (AMSLVR-360)
- Large Result Files in Gravity-based Filling Simulation
- In gravity-based filling simulations, you can specify a point where the level of liquid should be maintained. In these analyses, the solution was printed at every time step to the result files, making these files very large. This issue is now resolved by adding intelligence to the solver and printing the results only in those steps where it is relevant (and changing). The target is to restrict these result steps to around 100 steps. (AMSLVR-366)
Injection Molding (3D)
New Features
- Fast Packing Solution Module
- A new fast packing solution module is added in this release to support the packing analysis of thin injection molded parts. The fast solution supports the filling, packing, and cooling stages of the molding process. The fast solver is recommended for meshes containing a single layer of elements through the thickness. (AMSLVR-225)
- Fast Fiber Orientation Analysis
- A new fast fiber orientation analysis is added to the solver to enable fiber orientation computations in an MPI parallel computation environment. With this new algorithm, the performance of fiber orientation analysis using OpenMP is also improved. This is used with the detailed version of the filling solver and requires a mesh with four or more layers through the thickness. (AMSLVR-373)
- Warpage Analysis with Fibers using Multiscale Designer
- The warpage analysis is enhanced to utilize multiscale designer (MDS)
material data while computing the warpage of fiber-filled polymer parts.
Without user intervention, the solver now:
- Writes all the necessary input data files.
- Launches the OptiStruct solver to perform structural analysis of the fiber-filled polymer parts using OptiStruct and Multiscale Designer.
- Volumetric Shrinkage Result
- A new contour plot for volumetric shrinkage result is added to the packing stage as a transient nodal result. (AMSLVR-24)
Enhancements
- Improvements to Sink Mark Computation
- Significant improvements are made to the sink mark computations. (AMSLVR-199)
- Error Diagnostics
- The solver issues an error message and terminates the computation if it takes an unreasonably long time to compute the solution due to data errors. (AMSLVR-359)
- Mesh Quality Check Warning Message
- The solver prints a warning message in the *.out file when the given mesh does not meet the specified quality requirements. The solver continues to solve with the given mesh, but the accuracy of results may be affected. (AMSLVR-353)
Resolved Issues
- Packing Analysis using Constant Time Step
- An error when using constant time step during the packing stage is resolved. (AMSLVR-383)
- Issues in Cooling Simulation
- Under some conditions, the cooling solution was taking more time and was not accurate. Now the simulation is faster and more accurate. (AMSLVR-227)
Welding
Resolved Issues
- Inaccuracies in Simulating Curved Weld Path
- The heat source path was not correctly computed when a weld path is curved instead of a straight line. This issue is now resolved by interpolating the curved weld path to correctly guide the heat source movement. (AMSLVR-364)
- Error Message when Opening H3D File
- There was a minor attribute issue in the H3D file that resulted in an error message while importing the H3D file. This issue is resolved. (AMSLVR-305)
- Removed Unrelated Results in Fast Distortion Analysis
- The welding solver supports three different analysis types and each with its own set of results. The H3D file contained results that were not relevant to the computed analysis type. This issue is resolved by writing the results that are specific to the computed analysis. (AMSLVR-296)
Known Issues
The following known issues will be addressed in a future release as we continuously
improve the performance of the software:
- The stress results in the coupled analysis are based on the linear thermal elastic material model. It is not suitable to predict the residual stress after a welding model is cooled down to room temperature. This will be addressed in the upcoming releases by supporting elasto-plastic material models.
Polymer Material Data Analytics (PMDA)
Altair Manufacturing Solver and HyperXtrude solvers support polymeric manufacturing processes such as injection molding, polymer extrusion, and resin transfer molding. Most manufacturing engineers and scientists spend a lot of time on the material data to mine valuable information and key insights on its behavior. The main goal is to encapsulate this intelligence into a package for data mining and analytics.
New Features
- Level 0 – Material Data Validation
- PMDA checks the material JSON file and determine if it has all the necessary data. It then determines if the material is suitable for filling, packing, cooling, and warpage analysis stages.
- Corrected Material Data
- PMDA attempts to fill in some of the missing data. This is an experimental feature and will be improved in the coming releases. Corrected material is written as a new file and the quality report indicates the details of the assumptions made.
- Level 1 – Material Data Validation
- PMDA checks the material JSON file based on the known rules to determine if the data is correct. It then determines if the material is suitable for filling, packing, cooling, and warpage analysis stages. The rules checked are not exhaustive and they will be improved every release.
- A Material Data Report in PDF Format
- A PDF report of the material is generated based on the given data. This report includes plots for viscosity, equation of state, specific heat, and thermal conductivity. It also includes the model equations.
Known Issues
The following known issues will be addressed in a future release as we continuously
improve the performance of the software:
- PMDA supports only Cross and Carreau-Yasuda viscosity models.
- PMDA supports only WLF and normalized-WLF temperature dependence models.