RokHodnik

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Posts posted by RokHodnik


Hello!
I would like to apply forces in the inside of an toroid body. I find command to apply constant amplitude forces. But I would like to apply forces that have amplitude depending on the angle and their dependence is sinusoidal.
For better understanding I am attaching the figure below.
Thanks for your help.

@Rahul Ponginan thank you.
So if I understand correctly when observing acceleration of a point of a structure it is in unit mm/s^{2}?

+ how to export plot data to .csv format?solved 
Hello!
I am post processing results in HyperView from SimLab. I used the build plots feature to draw a plot of frequency dependancy of node acceleration on model. I get the below graph.
What is the output measurment unit? Is it m/s^{2} or something else?
Thank you,
Rok Hodnik

Still no success.

15 hours ago, Alessio Librandi said:Dear Rok,
Altair SimLab does not have yet explicited units of measure, but this enhancement will happen very likely in the next release (SL 2019.2).
Until then, please consider to adopt always consistent system of units. You can follow the guidelines I attach here.Thank you
Attatchment unavailable.

@Rahul R yes it would be convenient.
Still waiting on your reply on my other topic of acoustic analysis ...

Thx for help @Rahul R.
I think Altair should consider adding unit labels next to the input boxes.
If there is no unit label user would expect SI units so you can easily get confused with critical parameters.

Calculating Mass property confirms the 7.65e6 kg/mm^3. Please confirm my statement.
The modeled structure sholud have cca. 200g of mass.
Input density in this case is 7.65e6 kg/mm^3.
Still confused with tutorial input data and default input data in the box. As 7.8e9 density is not used for any material why should it be default value...

Hello!
One quick question.
When inputing units into materials manager in Simlab I often have problem with knowing in what units to input the property data.
For example is the unit for Density kg/m^3 or g/mm^3 or kg/dm^3 or kg/mm^3?
In tutorials people are usualy inputing data in XX units for example for steel 7.8e9 units.
Steel has:
7650 kg/m^3
0.00765 g/mm^3
7.65 kg/dm^3
7.65 e6 kg/mm^3
So what is the input unit?? I think it is kg/mm^3 but then tutorials input false data.
Specific density SI unit is kg/m^3.
Below is example from tutorial.


@Rahul R did you maybe manage to solve the error?
If i ignore the above mentioned problem and proceed the video tutorial I get this error message that I think is connected with the node separation problem listed above.
Error in Output window:
Face ID : 6762, Cad ID : 153, Body ID : 6022
Area : 11018.9
Number of Edges : 26
Color : 0, 0, 0Validating the bolt edge "7044".
Identified as through hole.
Validating the bolt edge "7040".Identified as through hole.
Validating the bolt edge "7030".Identified as through hole.
Creating RBEs and Bars for the bolt edge 7040.
Matching bolt edge is 6972.
No slave node is found for matching edge. Check scale factor/RBE diameter. Failed to create head.
Creating RBEs and Bars for the bolt edge 7030.
Matching bolt edge is 6970.
No slave node is found for matching edge. Check scale factor/RBE diameter. Failed to create head.
Creating RBEs and Bars for the bolt edge 7044.
Matching bolt edge is 6982.
No slave node is found for matching edge. Check scale factor/RBE diameter. Failed to create head.
Thanks!

@Rahul R I have hit a problem again that I am not able to solve myself. What could be the problem? When I try to separate nodes I get this message that I think impacts the further process.
Attaching Simlab file below.
Thank you!
The message box should say: Separate nodes completed.

Sure, I am following proposed tutorials for geometry and mesh. So far no problems occurred until this.
Thank you very much for your help!

When following video tutorial I hit an error that I was not able to solve myself.
When applying Volume Mesh command to the bodies this error message appears:
I am using SimLab 2019.1

@Rahul R still not able to get any info how to generate fluid mesh and place microphone at node locations.

@Rahul Ponginan @Hyperman @Pranav Hari @Abdessamed can anyone of you help me with above mentioned challenge?
Best regards,
Rok Hodnik

@Rahul R is there any chance to get a tutorial of acoustic noise setup in SimLab (placement of microphones and fluid mesh generation) and then acquiring the results in frequency domain? I would like to gain results as shown on the image below.
Or if an tutorial does not exist could you share with me finished SimLab and HyperView project?
Best regards,
Rok Hodnik

@Rahul R thanks for the link.
I still need some help on extracting data of ERP and acoustic noise.
Thank you!
Best regards,
Rok Hodnik 
This tutorial of analysis using HyperMesh is useless. It only shows steps to the point of forces export from Flux. With additional tutorial ''HowTo_OptiStruct_Flux'' you can progress to the point of displacement, stress and load output. Is there any posibility to get a tutorial on how to proceed from this point?
All of the tutorials seem to be dealing only with the problem to the point marked with red.


Hi!
I am a beginner in the Altair package. I am working on topic of vibroacoustic analysis of emotor. Currently I am dealing with basics and struggling to extract acoustic noise from HyperMeshOptistruct analysis. I followed a tutorial on how to export electromagnetic forces from Flux to HyperMesh and then perform freq. response analysis. I manage to extract data about displacement and stress and view the results in HyperView. But I am not able to find any tutorials on topic of vibroacoustic analysis of emotor.Can anyone reference me a good tutorial to follow to achieve this analysis? In further work I would like to close this analysis in an optimisation loop to optimise the noise level with preservation of other electromagnetic performances.
Thank you!
Best regards,
Rok Hodnik 
Hello!
I am trying to run an analysis of a solid model based on steps described in ''HowTo_OptiStruct_Flux'' tutorial included in the tutorial install directory. I want to make an vibroacoustic analysis of an electric motor based on imported forces from Altair Flux. Currently dealing with basics and I want to make analysis on a simple motor from Flux Overlay import. I have assigned mesh, load steps, materials and constraints as in the tutorial, but I got quite a few errors. Some of them I have already managed to solve thx to this forum.
Now I ran into a problem below, that I cannot find a solution online or cannot solve it myself. Full error text in attached file.
*** ERROR # 2784 ***
Solver failed in the eigen solution of reduced order model,
due to the illconditioning of the FEA model.
Please check if there is any message about mechanisms printed above,
make proper fix and rerun with it.Some other possible causes and solutions:
1. Solver may fail due to extreme large upper bound in EIGRL/A card.
Reduce the upper bound.
2. Solver may fail due to nearly rigid body modes:
Set PARAM,RBMEIG to be higher than the eigenvalue of the highest
rigid body modes.Thanks for your help.
Best regards,
Rok
Sinusoidally distributed forces
in Altair SimLab
Posted · Report reply
@Alessio Librandi thx! Bearing pressure is exactly what I needed!