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HyperMesh CFD: Known Issues
List of known issues that were discovered after release. (Note: This article will continuously be updated when issues are reported)
HyperMesh CFD 2023.0 known issues:
Geometry - Meshing
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Manage tool: Manage tool in Simulation ribbon does not list meshing or runs residing in same folder as hmcfd file.
Workaround: You have to submit meshing or AcuSolve job to review the list.
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Right click -->Reverse displayed for Geometry and FE geometry data is not working properly. Works fine for Lite and Discrete data.
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Busy cursor: Busy cursor does not come up for few tools like CAD Wrap.
Work around: Moving mouse cursor to browser or ribbon area may bring back busy cursor. Wait till you see message at bottom like "Wrap Mesh End"
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Import Solver decks: Importing with All(*.*) filter in dialog causes import failure randomly.
Work around: Select file filter first and then select files in the dialog
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CAD Wrap – higher overlap tolerance value:
High value compared to model dimension values of overlap tolerance can distort model.
Work around: Define very small value for overlap tolerance
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CAD Wrap - Quality cleanup option can distort shape.
Work around: Turn off Quality cleanup option, use any repair tools to improve quality separately.
Caser Setup (Aerodynamics and Aeroacoustics):
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Section cut inclination is not reset on selecting new base plane. Multiple transformations can also lead to an incorrect normal.
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Importing template file with overset fan volumes can throw a warning without any parts mentioned in the dialog.
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MRF fan parts are not written to the xml and stl files correctly.
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Aerodynamic coefficients plot background is black and cannot be modified.
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Resizing belts does not result in the correct graphics rendering or collision calculations.
Post Processing:
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Plots - Rake/Intersection: AcuSolve derived data fields: Known to cause application to crash when fields are read in from AcuSolve direct reader, for Derived or Miscellaneous fields.
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Signal Processing - Probe: The window overlap must be defined as the integer value of sample points of the overlapping size(i.e. block size= 1024, window overlap=512 for 50% overlap).
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Signal Processing - Surface - Integration: OASPL needs to be computed using p**2, not SPL, use Calculate toolset to recompute from SPL and then integrate.
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HWCFDReport Automation - GSP - Surface: Definitions for view, colormap and background_color are not honored. The user is requested to manually Open/Import the resulting .gsph5 file into
Re: Change medium properties in Altair Activate Modelica Thermal
Hi Tomas,
Custom media can be declared using the Medium block and referencing it in all the thermal blocks.
Look at the example I've attached and notice the block called Custom Medium and how all the thermal blocks reference it with "FromModelica('/Custom Medium')". If you play around with any medium parameter, you'll see changes in the simulation.
Hope this helps.
Rafael
Re: How do I configure regional date formats?
Hi Daniel,
The SAS language includes a number of options to control the layout of dates, but I'm not sure whether your problem relates to MS Office, Altair SLC, or the way you are importing the Excel data.
Anyway, the SAS national options are:
- LOCALE=en_GB (also en_US, fr_FR, fr_BE, fr_CH, de_DE, de_CH, hu_HU), which controls language, dates, currency, etc.
- DATESTYLE=DMY (also MDY, YMD, LOCALE), which controls only reading and writing dates.
- You appear to be using a default of DDMMYY8.
- Others include MMDDYYw. YYMMDDw., DATEw., NLDATEw., MONYYw., etc., where w=width.
Re: Decision Tree - only one attribute per branch?
Hello,
Certainly! In a One Rule decision tree:
Select Best Attribute:
- Evaluate each attribute's classification error.
- Choose the attribute with the lowest error.
Create Rule:
- Formulate a rule based on the selected attribute.
Apply Rule:
- Classify instances based on the rule.
Repeat for Each Attribute:
- Iterate through all attributes to find the best rule.
Choose Best Rule:
- Select the rule that performs best on the data.
Tree Structure:
- The decision tree has a single level, with branches corresponding to attributes and leaf nodes representing predicted classes.
Example in Python (using scikit-learn):
<p>from sklearn.tree import DecisionTreeClassifier, export_text</p><p><br></p><p># Create a One Rule decision tree</p><p>tree_clf = DecisionTreeClassifier(max_depth=1)</p><p><br></p><p># Train the classifier</p><p>tree_clf.fit(X_train, y_train)</p><p><br></p><p># Display the selected rule</p><p>tree_rules = export_text(tree_clf, feature_names=iris.feature_names)</p><p>print(tree_rules)</p>
Re: Decision Tree - only one attribute per branch?
I got an email from Free Altair Student Edition but can't download the program from the link in the email pls help
Evan Ch
Re: Resource "Limit:<username>_setname_<limitcount>" remains in system forever, how to make it expire after certain # of days?
From what I understand, the answer is no, we don't have what you were looking for because it's created on the fly. What can be done is to run a vovcron/liveness that runs “vovforget -oldlimits” on a daily basis. This was what other customers had done and it worked well.
Cary Wei
Re: How to peform FEA on Triangular Mesh derived from an Implicit model?
To run analysis on triangular mesh parts you need to choose the SimSolid solver. That is under File/Preferences/Inspire/RunOptions.
To control the faces generated during the conversion to triangle mesh you can adjust the break angle under File/Preferences/Inspire/Modeling Space /Discrete Modeling.
You can see in this example the break angle was reduced to avoid merging the fillets and flat faces.
Re: How do I access DCONADD through Hypermesh interface? I am trying to run optistruct optimization while turning on/off certain responses & constraints.
You could od this 2 ways, at least:
The the optimization view/browser to create and manage different optimization problems/scenarios, with different constraint sets.
Or using the Entity State Browser to activate/deactivate export of your constraints.
How to reduce penetration
Hello,
May I ask your favor regarding contact and reaction force?
1. Regarding contact (penetration)
1-1) I am solving excavator model which is passing over blocks. As you can see in below picture (section cut view to see penetration) there are several penetrations. I solved several times by changing contact stiffness K (F=K*z^exp) but those were not worked properly. I tried within 1000~3000 for K and time step 0.0005~0.0003 (too long solving time if use 0.0001). Can you advise me how to reduce penetration?
1-2) As you can see in picture in below right, too much penetration was made for 0.01 second. There are around 50 sub steps between 4.94 and 4.95 second. And average step size is 2.44E-5. Should I reduce step size more? or is there any reason and countermeasure for this kind of result?
1-3) I saw Advanced option panel for contact in MotionView. Is this helpful to resolve above problem? I tried with checking them but I was faced an error. Could you explain me the function of the option? or Could you let me know the link describing detail explanation?
2. Reaction force
I am comparing Roller's reaction forces between test and simulation. Reaction force by simulation is 2 or 3 times higher than that of test. All parts are composed by rigid body, including ground. Length of ground is around 30m and I installed bushing(3E5N/mm for translational, 1E15N/mm for rotational) on the ground to reduce reaction force but it was not enough to reduce reaction force (ground deflect too much if use weaker bushing). Do you have this kind of experience? and could you share the experience how did you resolve this kind of problem (very higher force than real)?
Thank you and Merry Christmas & Happy New Year.