Dynamic Crash Analysis - Hypermesh Tutorial

Are you a FEA hobbyist wanting to learn Altair Hypermesh ?
Are you annoyed by the dearth of good Hypermesh tutorial videos ?
In that case, you just came to the right place !
This video explains the complete process of performing a dynamic crash analysis in Altair Hyperworks using the robust Radioss solver.
Prerequisites ? None !
Right from importing the geometry to complete solver deck setup, this video will guide you in every step so that you achieve the perfect results for your design.
Although the learning curve for Hyperworks is steep, this video provides all the required information in a concise manner so that you know why you are doing every step in the setup!
So sit back and enjoy!
If you find this video helpful, kindly hit the thumbs up and subscribe to Aeroswap for many more amazing tutorials!
CAD Model File : drive.google.c... #aeroswap #fea #hypermesh #cae

[@adamchelchowski]

Hello Sir, I have never seen more educative form of FEM than Yours. Best regards and thank You for all of them.

[@Aeroswap]

Thank you for watching. I'm glad it was helpful !

[@ayushkaiwart2451]

your videos are easy to understand . thankyou

[@nikhilraval41]

best explaination ever :) tysm Sir

[@kenkim2687]

Hello, thank you for this educated video. I hope you will upload crash examples more! This is the real life problems and you did a great job explaining well

[@Aeroswap]

Thanks Ken! I'm glad you found this helpful. Will be posting more content about crash testing in the future.

[@arthurfranklin7045]

Thank you very much for your help

[@sathishkumarelango1174]

Very useful for my project works. Thanks bro

[@Aeroswap]

I'm glad you found my videos helpful !

[@bhupeshparate999]

Awesome Sir

[@rockingstar8899]

Great tutorial very useful, Bro at 4:52 we can use auto midsurface

[@Aeroswap]

Yes definitely. Go for it. It auto option fails to extract all the midsurfaces, you can use the method that I showed.

[@rockingstar8899]

@@Aeroswap ok bro thank you very much 😇

[@abhishekborde1219]

please do videos more on post-processing of crash analysis

[@Aeroswap]

A new video on crash analysis will be out soon. Make sure to keep the notifications turned on to get updates instantly!

[@emanisuresh8219]

Firstly, the tutorial was amazing..though, the properties and other required parameters entered without explanation..i hope there is a video on how to enter or select those values and also those card images.. thanks alot sir,, useful information..

[@Aeroswap]

Agreed, the parameters and cards need to be explained in detail. I will work on follow up videos which will focus more on the parameters rather than the setup process. Glad you liked the video :)

[@emanisuresh8219]

@@Aeroswap i loved it bro.. its not just the content to be encourageable. But also ur support even after long time posting of the video.. hats off to you..

[@paramveerpatil6607]

KEEP IT UP, BEST LUCK

[@Aeroswap]

Thank you!

[@pearcegibson4521]

Great Video. However, I am facing a problem where 'BCs Manager' does not appear in my 'tools' section. Is there any other way of finding it? Thanks

[@Aeroswap]

Hello Pearce, did you try searching for it using Find option ? Press Control+F and type 'BCs'. In the list, you will see BCs Manager. Then you can access it. Which version of Hypermesh are you using ? In older versions, BCs manager was included in the Utility menu. Please check the same for your software. Hope it helps!

[@nunavathprakash8869]

While creating the rigid wall it is getting created in groups tab of model tree, how can I get rid of this..?

[@megharao6079]

Thanks for uploading the content on Radioss Solver ,sir could you please upload videos on Optistruct as well.Thank you in advance sir..

[@Aeroswap]

I have posted a 2-part tutorial on Structural Analysis using Optistruct. Do check that out from the channel page.

[@megharao6079]

@@Aeroswap thank you sir,👍

[@saswatpradhan8320]

Sir can u please make a video of crash test of composite materials in radioss

[@Aeroswap]

Yes, I am working on it. Will post the tutorial soon. Thanks for the suggestion though!

[@nunavathprakash8869]

I used one model for static structural analysis, can i use same model for this crash analysis also

[@JeonJungkook-xj8wg]

Tools -bc manager is not available in the panel is there any other way to give initial velocity ??

[@namanjaohari5189]

can u help me with this error ? error id : 119 ** error in interface definition description : -- interface id : 1 -- interface title : contacts lagrangian surface is empty

[@Aeroswap]

Hi Naman, do not use second order elements. Type7 contact is not compatible with second order elements and gives this error. You can change the element order from 2D panel. This will resolve the error. I hope this helps!

[@namanjaohari5189]

@@Aeroswap thank you so much sir!! it helped!!

[@SKULLCRU5HER]

Nice and informative video, can we expect a pendulum impact test as per SAE J2420 OR ECE R29 OR AIS 031?

[@AlbertCM1199]

Hello, thank you so much for the video. I have a question: why you haven´t defined a material failure in this simulation? Thank you in advance!!!

[@namanjaohari5189]

sir, why does the total energy line in the graph slightly decreases instead of being a straight line?

[@Aeroswap]

Due to some inaccuracies in model setup and element formulation, total energy is not conserved. Sometimes, it is lost to hourglassing. Hence, the total energy line is not straight.

[@gumuso92]

Can you see how to create a force failure criteria for bolt beams . For example M8 10.9 quality bolt have certain load capacity acc. to ISO-898-2 document. So how we can set this value for bolts in Radioss. Very thanks

[@Aeroswap]

Hello, If you output the 1D stresses/strains for all beam elements, you can just refer the value and compare it with the failure limits to check if the bolt failed. In this case, you will not see the animation of bolt failure. If you are more interested in visualizing the failure, you have to use solid elements (3D) to model the bolts. Then specify a material failure criteria for element deletion. This will also require the creation of contacts between bolt and mating components. Finally, the modeling approach depends on what information you are expecting to gain from the analysis. I hope this helps.

[@gumuso92]

@@Aeroswap I just mean failure in 1D Beam, so I need to see failure because of I do not want to the failed bolt dont still carry the load after its capacity is exceeded.

[@Aeroswap]

You can create a material failure and assign it to the bolt component. As soon as the failure limit is reached, the bolt will get deleted as required.

[@thekiryl1213]

Hello. I would like to ask, which car is this chassis from ?

[@billifer654]

Awesome tutorial! I am having some difficulty when u reflect the mesh symmetrically. Basically when I reflect the mesh, the mesh just moves to the other side (and deletes the original mesh). Any ideas?

[@Aeroswap]

You forgot 1 small step! When you select the elements, click on the selection box again and then select 'duplicate'. Select the 'original component' to store duplicates. This will duplicate all the selected elements and reflect them to the other side.

[@billifer654]

@@Aeroswap AH yes it worked! haha thanks dude. btw u an ME im assuming?

[@Aeroswap]

Not yet. I'm a final year BE student. Will graduate next year!

[@masse6673]

Thanks for the useful video👌 unfortunately, after I run the simulation there are no Animation Files generated. Any ideas what could be my mistake?

[@Aeroswap]

Make sure that the ENG ANIM DT card is properly defined. This card controls the animation file output. As a general rule, specify the animation time interval value as 1/100 * runtime. This will create 100 animation frames for the analysis.

[@saurabhsahane1365]

CAE Guru 🙏👍

[@sanketargade3685]

Sir how can i download final analysis report?

[@jashanramsurn9514]

Nice tutorial! One thing I don’t quite understand though. How can you define the master and slave component to be the same? I’m having issues on my side doing that.

[@Aeroswap]

Hey Jashan, in this particular case, we have a rigid non-deformable wall. Hence you can get the same results even if you only select the wall as master and chassis as slave. But we can also use a non-rigid wall to simulate a more practical case. It is important to select all the nodes both as master and slave in that case. This is because the chassis will deform the wall, just like the wall deforms the chassis. To avoid confusion, it is always better to just select all the nodes as master and slave. I hope this clears your doubt.

[@jashanramsurn9514]

Aeroswap Thanks for the explanation. I understand your approach now towards the non-rigid wall for a more realistic case. How did you then define the wall to not be rigid? Is it automatic since the master nodes are not defined from it?

[@Aeroswap]

Just making these changes in the contact is not enough. As we used the 'Rigid wall' option to create the wall, it is rigid no matter what. If you want a non-rigid wall, just create a vertical surface at the position of the wall and apply 2d mesh with proper material and thickness to it. Then it will work as a deformable wall driven by the contact.

[@jashanramsurn9514]

​@@Aeroswap Understood but I'm currently getting error IDs 558, 611 and 343 regarding interface definition (master surface) and initial penetration (interface) although I followed your exact instructions (using my own model). That's why I thought maybe it had to do with master and slave components being the same but it worked for you.

[@Aeroswap]

From what you are stating, this is not a contact problem. As you have got the initial penetrations error, there are elements intersecting each other in the model. You can use the intersection and penetration check to resolve this. Or simply delete the element with ID stated in error message and recreate it.

[@pritishsadhale1560]

Thanks👍

[@anirudhkohli1626]

Can you please share the CAD file

[@muizzjamal8871]

Having trouble in translating the node. It just elongates the small box and node disappears. Please help

[@Aeroswap]

Hi Muizz, This is a very common mistake and easy to rectify. When you select the node, click on the selection box again and select 'duplicate' option. This will create a temporary node and not distort the geometry after translation operation is performed.

[@muizzjamal8871]

@@Aeroswap Yeah solved it. Thanks man!

[@sushantS_24]

what is the difference between results you observed in Lsdyna and radioss ??

[@Aeroswap]

If the modelling method and mesh quality is same, the results should be exactly similar with both solvers.

[@ek121b]

why when I import the .iges file I have 17 components instead of just one?

[@Aeroswap]

Hello, you can use the 'Organize' tool to merge the components into a single one. After that, you can simply follow the video for analysis setup!

[@rajanarjunsharma9474]

Hello Sir.... I am new to hypermesh. I have installed hypermesh but when I click on Radioss to run the analysis, it is giving error as 'Radioss is not installed currently' plz help me out...

[@TARUNKUMAR-wp6gt]

Hi how did you solved this issue same issue I am facing radioss solver is not installed how did you installed

[@HawkinsOkeyoEng]

Hey, I was wondering if you have some spare time to have a quick look at a model in which I happen to be getting different values depending on the time step chosen. It is a very simple model which I can send you. let me know ASAP. Thanks in advance!

[@intern1863]

Im using 2020 version , setting up the BC's are little tedious , can you help me with it ?

[@Aeroswap]

Yes, the setup method is different in the newer versions of Hypermesh. Please follow this video for the new setup - kzbin.info/www/bejne/Y5vYZHx_os9gpJI

[@intern1863]

@@Aeroswap Thank you soo much for the video and the acknowledgement

[@batman1626]

sir how can we perform two rollcage crash analysis? i am trying to perform it from severa days

[@hariharan419]

Thank you for this video sir it is very useful 👍 I have finished the solver deck file, sir but after running it in Radioss, i am getting error like this Error Id : 286 ** Error in Input Consistency Description: Quad are not compatible with N2D3D=0

[@Aeroswap]

Check your mesh quality. This might solve the error. Let me know if it doesn't work!

[@hariharan419]

ok sir i will check it

[@sanketargade3685]

how can i check mesh quality?

[@Aeroswap]

Using the element quality check panel. Tools >> check elem

[@sanketargade3685]

It's shows expected 99%, then what i do?

[@suprithsrivikat9]

How did u stitch the engine hood? I cant do it with the toggle tool..i tried making a surface in between them..but that didnt work out

[@Aeroswap]

Try increasing the tolerance value and toggle again. If the gap is large, the default tolerance value may not work.

[@suprithsrivikat9]

@@Aeroswap I have tried it using 5 tolerance value...still doesnt work! kindly help me with this!

[@Aeroswap]

If possible, try deleting the surfaces and create them again using the 'Ruled' option in surfaces tab.

[@suprithsrivikat9]

@@Aeroswap That worked thank you very much! It would be nice if u made CAD tutorials coz the design is super good!!

[@Aeroswap]

Good to know it worked! I am not a CAD expert, that design was actually made by a friend of mine :)

[@TaiChick]

Hello, I do like your video but I have warning id 343, did u have a way to solve it?

[@Aeroswap]

Can you elaborate on what the error message says? Then I can suggest possible changes to resolve the issue.

[@TaiChick]

@@Aeroswap i fot error KMP_Stacksize less than 380M and some warning, WARNING ID : 343 ** WARNING : INITIAL PENETRATIONS IN INTERFACE .. RIGID WALLS .. ELEMENT BUFFER INITIALIZATION .. GEOMETRY PLOT FILE .. PARALLEL RESTART FILES GENERATION TERMINATION WITH WARNING

[@Aeroswap]

You have penetrations in your mesh. Some elements are intersecting each other, this is not allowed. Please use the 'Interference and penetration checker' to find faulty regions in the model to correct them.

[@TaiChick]

@@Aeroswap thank you

[@s.s.divakar7911]

sir for me the car just penetrate over the rigid wall without crashing it

[@Aeroswap]

Check the normal vector of the rigid wall. This can be done by reviewing the rigid wall from model browser (R-click >> Review). The crash will only occur if the normal vector is in the direction of the car. Otherwise it will not work! Secondly, also check whether you have correctly assigned the slave nodes (car nodes) to the rigid wall.

[@s.s.divakar7911]

@@Aeroswap ok thank you for your support

[@Know_l_edge]

what is unit of energy, mJ stands for ?

[@Aeroswap]

In the IS unit system, the unit for energy is Joule (J). Based on the unit system being used for the analysis, a muliplying factor will used to convert the energy value. The base unit will remain the same ie. Joule (J). mJ represents milliJoule

[@yatheeshwarsekar8016]

how do we calculate the runtime for crash analysis

[@Aeroswap]

Total run time is addition of time required for the chassis to reach the wall and almost equal bounce-back time to capture post-crash results.

[@yatheeshwarsekar8016]

@@Aeroswap is there any formula or procedure to calculate termination time

[@raghuramk1231]

Can u help me error 1109

[@anirudhkohli1626]

What errors will we face if we use auto mid surface instead of final edit tool?

[@Aeroswap]

There are 2 main things that could happen if auto midsurface is used on complex geometries - 1. Midsurface will not be extracted for some regions. Then you have to extract manually or create filler surface using geometry panel. 2. In case the surface pair is highly curved and twisted, the midsurface generated using auto option will be extremely warped and distorted. Using such a surface will greatly affect the element quality during meshing. In case of simple geometries with less number of curved surfaces, auto is the best and quick solution. But for complex and large geometries, I would always recommend going for manual extraction. Hope this clarifies your doubt!

[@everythingtamil1583]

Hii can you provide me the final output document

[@anirudhkohli1626]

Can you please share the CAD file

[@Aeroswap]

Hey Anirudh, I have updated the description with download link for the CAD model. Please check. Apologies for the inconvinience!

[@anirudhkohli1626]

Thank you Aeroswap for the CAD file and your efforts till now .

[@gauthamd3895]

In tools the boundary conditions is not given for me any suggestions?

[@shritejdeshmukh1591]

I am facing problem with generation of Animation files. When I click on radioss, the radioss process ends at Radioss starter. The radioss engine does not start. Please help.

[@Aeroswap]

It seems you have some error in the setup. In the working directory, there will be a text file with '.OUT' extension. This file stores all the information about the setup. If you view this file using any text editor, you might see some error messages. Then you can debug the setup accordingly. Hope it helps!

[@shritejdeshmukh1591]

@@Aeroswap Sorry, but can you please explain in a better way as I am new to Hypermesh and have never used Radioss

[@Aeroswap]

Okay. Open the folder in which you saved the model before running the analysis. There you will find several files have been generated. Open file with extension .out using notepad. The error you are facing will be listed here.

[@shritejdeshmukh1591]

@@Aeroswap Thank you! I solved the errors. 😊

[@Aeroswap]

Glad it worked! 👍🏻