Sir, It's just a phenomenal effort to demonstrate the method of doing crash analysis (You are right! The method of doing this analysis remains same for all kind of Frontal crash tests, so doesn't really depend on speed of the car body! Speeds are only the number given as in the form of velocity of the car body, so it can be changed easily as the Simulation Engineer wants!), so I truly appreciate your efforts of doing all these! But according to me there are several errors / unrealistic values in this analysis! They are as follows: Please correct me, if I am wrong! :) 1. The car body thickness is given as 2mm, which is too much...I guess! Generally, it is max. up to 1.2mm! 2. Mostly the small problem of car crash "Energy-absorption-system" is tested by this method, because for this Energy-abortion-system only one small crash-box is used (which is just a small sheet-metal box and having thickness up to 0.8mm) - It's BC is also easier to input, one end fix and the other end is given either velocity or load-case (Impact load or Static load) 3. The velocity you have given is 90,000 mm/s, which is equal to 324 km/hr!!! Normally, the max. Crash speed according to, Euro NCAP & IIHS (The Insurance Institute for Highway Safety, USA) are up to 64kmph with 40% Barrier Collision = 40mph = 17777 mm/s! Euro NCAP is up to 50kmph with 100% Barrier Collision = 30mph = 13889 mm/s! US NCAP is up to 56kmph with 100% Barrier Collision = 35mph = 15556 mm/s! 4. The measurement time, you have given is 0.0007s, which is I guess unrealistic! Generally, it's max. up to 70ms preferred by some good Engineers! So, 70 ms = 0.07s! Because, crash Engineers tested data shows the actual crash finishes in 70 ms. I think, 0.0007 s is too small! 5. Somebody has asked that why there is a big deformation showing at rear of the car! It should be happened at front, but not happening, because, the bottom edges of the car structure is fixed (Given as fixed support)! Thus, the bottom is fixed and so all the crash impact force flows above the fixed part and thus frontal part doesn't get much deformation, instead all these impact forces flows through the side panels and try to deflect the rear trunk part (or rear window part) more as compared to frontal Bonnet part. Creating first Euler case, that is why it happens so!!! Conclusively, the analysis results are true according to the given data! But still the given data is debatable! 6. There some more factors being considered while doing Crash test, one of the most important factor is HIC values! HIC = Head Injury Criteria = Acceptable values up to 840! The best cars get up to 400 HIC value! Euro NCAP accepts upto 840 HIC value! HIC is the most important criteria, because the ultimate Goal of doing this crash test is to save the Occupants (Driver & Passengers) and this HIC directly depends on how good the crash Enegry-absorption-system is engineered! Once again than you, sir, for sharing us this information! Please do not consider me as a wrong person or something! There are no intensions to hurt you! It is just, I express what I know! Your contributions to make all these videos are rather more helpful and appreciable! All the data, I entered here of EURO NCAP / US NCAP / IIHS are according to the latest 2015/16 rules designed for crash testing by these three individuals! ;)
sir can you please explain me how to get the load applied on the object hitted by vehicle in explicit dynamics of workbench. please reply me sir. it is very helpful for me.
+GRS CAD/CAE Dera Sir , i accidently came across your youtube profile , really u r dong a great job and awesome tutorials; Sir need your help in analysis of monolithic isolation joint used in oil and gas industry, hope to hear from you soon ...since your contact isn't displayed kindly let me know how to contact you; akashdruva892@gmail.com
Great video. Explained in details. I have some frequent issue while running explicit dynamics. What if Ansys is throwing a large energy error message? Should I increase the value of energy error? Or should I correct meshing at that point? Thank you
Dear Sir I have some questions ask from you regarding above analysis 1.Why you are choosing both materials are linear? Car body should be nonlinear material . 2.What is the body interaction (frictional or friction less) between vehicle and barrier? and Why? 3.why didn't provide gravity on the vehicle? 4.Why you arrest vertical displacement?After hitting vehicle will bounce on all 6 dof.
Thank you so much for the video!! 1 small question..on what basis, you had assigned the thickness to 2mm and 3mm? (in real case thickness will be more)
Helpful video. But I have one question for the crash analysis, is there necessary to draw full sketch of car? or only can draw a bumper? Please reply me.
Hey it was really impressive video. I am trying to do similar in tubular form chassis and I am encountering many error messages in meshing "The surface mesh is intersecting or close to intersecting making it difficult to create a volume mesh" Could you please tell me how to avoid that?
thanks a lot for the video! im having some problems about adding accelerometers on the center of the car in order to plot a lateral, vertical and horizontal accleration against the impact time graph 1) Is it possible to do this in ANSYS? 2) Or what should i set in the solution? ( is it select the surface in total acceleration) :)
+Billy Wong Billy, create surface split @ locations which in which you wish to capture acceleration. In post processing you may try extracting acceleration at vertices of that split
hi sir, for my project i choose end time 0,00625s but it calculates 0,00005s becuse of that my object cannot reach the fixed support can u help me about this
this video is very helpful, can you upload video giving information about how to use different type of contacts and how to choose initial time step, minimum time step and maximum time step for different scenarios. that would be very helpful.
Great video! Everything is explained with minute details. I just have one doubt. Why is the deformation maximum at the rear of the car, isn't supposed to be minimum?
+GRS CAD/CAE What can be modified in the setup or in the design of the car body to make the results look closer to reality where maximum deformation can be seen in the front of the car. Kindly explain. Thank you
there is a problem......... in the engineering data section, i accidently closed the text boxes for material selection, now i dont know where they went, i can't assign any material to my chassis now, KINDLY REPLY.
I have a problem with solve " Found 830177 nodes. Retrieving elemental size data ..... Found 414853 elements. Failed. Too many nodes per element " my computer is core i5, 4GB of Ram How many nodes can I work with ? Looking forward your reply . thank you
While I doing impact analysis on cold formed steel elliptical hollow steel column I obtaining that as velocity increases internal energy developed is decreased what is the reason for this?
@@ANSYS-India Thanks for reply. But when I selected the whole column body I obtaining result like this( as impact velocity increaes the internal energy decreases) but while select single node in the surface of impact I obtaining the correct relation .that is as velocity increases internal energy also increases
halo, can you help me to aplying temperature in explicit dynamic ansys workbench? i only can do it in static structural, but i confusing when i want to apply it in explicit dynamic
i want to know the different between geometry surface and geometry solid. When we use geometry surface and geometry solid in ansys workbench. What is the different? thanks
Greetings! ! The geometry surface is used to create the shell elements or constant wall thickness objects like sheet metal formed components which are subjected to loads other than in plane loads like bending and twisting or multi directional loading, The geometry solid is used to create solid elements mesh for parts that do not have constant wall thickness and have un even material distribution like die casted components like casings of gearbox or engine, molded components. Also note that shell elements have 6DOF in translation and rotation, whereas solid elements have 3DOF in translation. Email:engineeringtutorsdesk@gmail.com Website: sites.google.com/site/feaengineeringdesign/
GRS CAD/CAE Thanks for your answering Now I have some problems about ansys workbench I have y branch model. It is created from multi parts: Pipes and mapping plates Thickness of pipes are 30mm, and thickness of mapping plates are 80mm and 12mm I want to ask: 1.Should I used Geometry surface or geometry solid for this model 2. How to mesh this model? 3. all the connections are welding, Can you tell me how to created contact region? thank you very much!
I am facing some problem while contacting one moving plate towards a line body. one end of the line body is fixed. While simulation an automatic connection generates but after simulation it shows no contact.
Sir vey good nd helpful tutorial. sir i wanted to ask a question about my analysis. i am doing tensile test of composite. sir which type of analysis should i do and i have velocity of ultimate tensile testing machine as input. how can i give tht in ansys as input.
For CAD models, pls send an email to this ID, engineeringtutorsdesk@gmail.com For more videos pls visit this Website: sites.google.com/site/feaengineeringdesign/
I obtaining the deformation vs time graph as increasing only Generally it should increase and then decrease why I m only getting it as increasing only??
@@ANSYS-India I increase time also first I take .03 sec then I also run for 0.1 sec as end time but these take too much time for running but the result remain the same as the graph is increasing linearly without falling
Mandar, V-m stress is also called as distortion energy theory, v-m is the equivalent stress of all three principal stress. Similar to equivalent stress the equivalent strain is again derived from principal strains.
sir i had a problem with meshing of a car body in explicit dynamics analysis . after meshing of the car body the components in the body gets collapsed so meshed object becomes like a unstructured object so please suggest me some tips for meshing of a surface of car body
@@ANSYS-India I actually gave input as shown in the video. It took me almost 20 hours to complete. But the results depict only to crash, bouncing back simulation is not acquired.
Paul, For more Tutorial Videos Click on the link below ANSYS Workbench ruclips.net/p/PLOahOE6DpL4qq_QxPHieAeVejzDP1yIYW ANSYS Multiphysics ruclips.net/p/PLOahOE6DpL4qojPO7_GkgkVC-cB8KFMeC Hypermesh ruclips.net/p/PLOahOE6DpL4puVylWdpHWRoGhIfswDc6T Creo Simulate | Pro Mechanica | ruclips.net/p/PLOahOE6DpL4qvb2Z0Ir8SwvUyv0qnRGH4 Creo Parametric Tutorial ruclips.net/p/PLC1voSxuLSym29Dt_xNnIJxBCtE-k9iul Pro E Wildfire Tutorial ruclips.net/p/PLLBsoJO8DYcVGLa_se2y5Ao0Vzwy6TUbz For online training on ANSYS Workbench | Creo Parametric & Simulate | Pro E Wildfire & Mechanica | HyperMesh | Contact: engineeringtutorsdesk@gmail.com
Sir, It's just a phenomenal effort to demonstrate the method of doing crash analysis (You are right! The method of doing this analysis remains same for all kind of Frontal crash tests, so doesn't really depend on speed of the car body! Speeds are only the number given as in the form of velocity of the car body, so it can be changed easily as the Simulation Engineer wants!), so I truly appreciate your efforts of doing all these!
But according to me there are several errors / unrealistic values in this analysis! They are as follows: Please correct me, if I am wrong! :)
1. The car body thickness is given as 2mm, which is too much...I guess! Generally, it is max. up to 1.2mm!
2. Mostly the small problem of car crash "Energy-absorption-system" is tested by this method, because for this Energy-abortion-system only one small crash-box is used (which is just a small sheet-metal box and having thickness up to 0.8mm) - It's BC is also easier to input, one end fix and the other end is given either velocity or load-case (Impact load or Static load)
3. The velocity you have given is 90,000 mm/s, which is equal to 324 km/hr!!! Normally, the max. Crash speed according to, Euro NCAP & IIHS (The Insurance Institute for Highway Safety, USA) are up to 64kmph with 40% Barrier Collision = 40mph = 17777 mm/s! Euro NCAP is up to 50kmph with 100% Barrier Collision = 30mph = 13889 mm/s! US NCAP is up to 56kmph with 100% Barrier Collision = 35mph = 15556 mm/s!
4. The measurement time, you have given is 0.0007s, which is I guess unrealistic! Generally, it's max. up to 70ms preferred by some good Engineers! So, 70 ms = 0.07s! Because, crash Engineers tested data shows the actual crash finishes in 70 ms. I think, 0.0007 s is too small!
5. Somebody has asked that why there is a big deformation showing at rear of the car! It should be happened at front, but not happening, because, the bottom edges of the car structure is fixed (Given as fixed support)! Thus, the bottom is fixed and so all the crash impact force flows above the fixed part and thus frontal part doesn't get much deformation, instead all these impact forces flows through the side panels and try to deflect the rear trunk part (or rear window part) more as compared to frontal Bonnet part. Creating first Euler case, that is why it happens so!!! Conclusively, the analysis results are true according to the given data! But still the given data is debatable!
6. There some more factors being considered while doing Crash test, one of the most important factor is HIC values!
HIC = Head Injury Criteria = Acceptable values up to 840! The best cars get up to 400 HIC value! Euro NCAP accepts upto 840 HIC value! HIC is the most important criteria, because the ultimate Goal of doing this crash test is to save the Occupants (Driver & Passengers) and this HIC directly depends on how good the crash Enegry-absorption-system is engineered!
Once again than you, sir, for sharing us this information! Please do not consider me as a wrong person or something! There are no intensions to hurt you! It is just, I express what I know! Your contributions to make all these videos are rather more helpful and appreciable!
All the data, I entered here of EURO NCAP / US NCAP / IIHS are according to the latest 2015/16 rules designed for crash testing by these three individuals! ;)
Thanks Ravi.
what a great effort for giving this comment!
sir can you please explain me how to get the load applied on the object hitted by vehicle in explicit dynamics of workbench. please reply me sir. it is very helpful for me.
I really appreciate your knowledge
Sir super
i am begging ansys from zero. U are the best teacher. Great job. Thank you for your effort.
Serhat, good to know the feedback, please keep sharing these videos to those who want to learn.
+GRS CAD/CAE Dera Sir , i accidently came across your youtube profile , really u r dong a great job and awesome tutorials;
Sir need your help in analysis of monolithic isolation joint used in oil and gas industry, hope to hear from you soon ...since your contact isn't displayed kindly let me know how to contact you;
akashdruva892@gmail.com
Thank you everybody for your valuable comments.
can i get geometry of car model
Great video. Explained in details. I have some frequent issue while running explicit dynamics. What if Ansys is throwing a large energy error message? Should I increase the value of energy error? Or should I correct meshing at that point? Thank you
Great video, thanks for sharing.
Dear Sir
I have some questions ask from you regarding above analysis
1.Why you are choosing both materials are linear? Car body should be nonlinear material .
2.What is the body interaction (frictional or friction less) between vehicle and barrier? and Why?
3.why didn't provide gravity on the vehicle?
4.Why you arrest vertical displacement?After hitting vehicle will bounce on all 6 dof.
Also explain, how to calculate step end time.
Hello Sir, can you please explain how to get convergence graph here?
Wow. Perfect explanation
Excelent tutorial ! Really helped me on my college study.
Thank you so much for the video!! 1 small question..on what basis, you had assigned the thickness to 2mm and 3mm? (in real case thickness will be more)
Helpful video. But I have one question for the crash analysis, is there necessary to draw full sketch of car? or only can draw a bumper? Please reply me.
+mamta pawar to what distance the impact will damage the parts, those need to be considered.
CAE Worldwide Sir if the car is impact on the rear bumper of the next car then which type of test will be there on the rear bumper
Hey it was really impressive video. I am trying to do similar in tubular form chassis and I am encountering many error messages in meshing "The surface mesh is intersecting or close to intersecting making it difficult to create a volume mesh" Could you please tell me how to avoid that?
thanks a lot for the video! im having some problems about adding accelerometers on the center of the car in order to plot a lateral, vertical and horizontal accleration against the impact time graph
1) Is it possible to do this in ANSYS?
2) Or what should i set in the solution? ( is it select the surface in total acceleration)
:)
+Billy Wong Billy, create surface split @ locations which in which you wish to capture acceleration. In post processing you may try extracting acceleration at vertices of that split
+CAE Worldwide for more videos visit ruclips.net/user/grscadcae
+CAE Worldwide thanks a lot!!!! :)
distance between bumper and impact is present but is there necessary to draw full car sketch?
Can we use a acutual 3d model of a real life car for this test
hi sir, for my project i choose end time 0,00625s but it calculates 0,00005s becuse of that my object cannot reach the fixed support can u help me about this
this video is very helpful, can you upload video giving information about how to use different type of contacts and how to choose initial time step, minimum time step and maximum time step for different scenarios. that would be very helpful.
Good explanation but why did you pick engineering material in explicit dynamics when explicit materials are available.
Great video! Everything is explained with minute details. I just have one doubt. Why is the deformation maximum at the rear of the car, isn't supposed to be minimum?
Yes you are right sidd, the structure is not stiff at back.
+GRS CAD/CAE irrespective of the stiffness, isn't is supposed to be maximum deflection in the front where it actually crashes.
+GRS CAD/CAE What can be modified in the setup or in the design of the car body to make the results look closer to reality where maximum deformation can be seen in the front of the car. Kindly explain. Thank you
Indeed this video is helpful. Is it possible to create video to save for desktop from Explicit Dynamics Analysis? Thank you!
great work thanks is not enough for your effort
sir, can you explain what does no of output points do and why did you set it as 100
Which generation of ansys workbench
there is a problem......... in the engineering data section, i accidently closed the text boxes for material selection, now i dont know where they went, i can't assign any material to my chassis now, KINDLY REPLY.
In my case, I followed the same step, and same conditions but, car moves in other direction after collision with little deformation.
I have a problem with solve
" Found 830177 nodes.
Retrieving elemental size data .....
Found 414853 elements.
Failed.
Too many nodes per element "
my computer is core i5, 4GB of Ram
How many nodes can I work with ?
Looking forward your reply . thank you
Sir could you please tell me how much time did it take to solve this.
While I doing impact analysis on cold formed steel elliptical hollow steel column I obtaining that as velocity increases internal energy developed is decreased what is the reason for this?
Just check the behavior, whether the bodies are interacting as expected
@@ANSYS-India Thanks for reply.
But when I selected the whole column body I obtaining result like this( as impact velocity increaes the internal energy decreases) but while select single node in the surface of impact I obtaining the correct relation .that is as velocity increases internal energy also increases
halo, can you help me to aplying temperature in explicit dynamic ansys workbench? i only can do it in static structural, but i confusing when i want to apply it in explicit dynamic
The time shown to solve the analysis is about 120 hrs .. plz help me on this .. y is it taking this much time
Thank you sooo much
hello,I used explicit dynamic to and i wanna know why i can't bounce back happening,thx
I need it bounce back happening,plz
i want to know the different between geometry surface and geometry solid. When we use geometry surface and geometry solid in ansys workbench. What is the different? thanks
Greetings! ! The geometry surface is used to create the shell elements or constant wall thickness objects like sheet metal formed components which are subjected to loads other than in plane loads like bending and twisting or multi directional loading, The geometry solid is used to create solid elements mesh for parts that do not have constant wall thickness and have un even material distribution like die casted components like casings of gearbox or engine, molded components. Also note that shell elements have 6DOF in translation and rotation, whereas solid elements have 3DOF in translation.
Email:engineeringtutorsdesk@gmail.com
Website: sites.google.com/site/feaengineeringdesign/
GRS CAD/CAE Thanks for your answering
Now I have some problems about ansys workbench
I have y branch model. It is created from multi parts: Pipes and mapping plates
Thickness of pipes are 30mm, and thickness of mapping plates are 80mm and 12mm
I want to ask:
1.Should I used Geometry surface or geometry solid for this model
2. How to mesh this model?
3. all the connections are welding, Can you tell me how to created contact region?
thank you very much!
My solution stucks at 30-40% when I press the solve button.
Any idea what I might be doing wrong?
Helpful video SIR
Sir can u please help me how to do an stress analysis on ladder chassis...
I am facing some problem while contacting one moving plate towards a line body. one end of the line body is fixed. While simulation an automatic connection generates but after simulation it shows no contact.
Sketch your problem description and send its snapshot to engineeringtutorsdesk@gmail.com. I will check and let you know.
Sir vey good nd helpful tutorial. sir i wanted to ask a question about my analysis. i am doing tensile test of composite. sir which type of analysis should i do and i have velocity of ultimate tensile testing machine as input. how can i give tht in ansys as input.
+Mza Nkh you can either do static structural analysis or explicit dynamic analysis. To initiate with, you can choose static structural
What is int_ energy in ansys dynamic analysis?
Thanks a lot this was very helpful. Can you provide a link where we can download the CAD model
For CAD models, pls send an email to this ID, engineeringtutorsdesk@gmail.com
For more videos pls visit this
Website: sites.google.com/site/feaengineeringdesign/
Why did you take no of points = 100 in Output Controls
I obtaining the deformation vs time graph as increasing only
Generally it should increase and then decrease why I m only getting it as increasing only??
Check by increasing the end time
@@ANSYS-India I increase time also first I take .03 sec then I also run for 0.1 sec as end time but these take too much time for running but the result remain the same as the graph is increasing linearly without falling
HI Nice informative video.
I've one query regarding von mises stress and eq. plastic strain....how it can be validated?
Mandar, V-m stress is also called as distortion energy theory, v-m is the equivalent stress of all three principal stress. Similar to equivalent stress the equivalent strain is again derived from principal strains.
Email: engineeringtutorsdesk@gmail.com
Website: sites.google.com/site/feaengineeringdesign/
GRS CAD/CAE
Ok but then we can't apply other theories like shear strain theories or total strain theories
Other theories are applicable to different material behaviour like, brittle behavior, ductile/elastic behavior and hyper elastic behaviour.
Mandar, Other theories are applicable to different material behaviour like, brittle behavior, ductile/elastic behavior and hyper elastic behaviour.
great job. thank you. really helped me a lot.
Good to know Atul, for more videos pls visit my website sites.google.com/site/feaengineeringdesign/
sir i had a problem with meshing of a car body in explicit dynamics analysis . after meshing of the car body the components in the body gets collapsed so meshed object becomes like a unstructured object so please suggest me some tips for meshing of a surface of car body
Send the snapshot to engineeringtutorsdesk@gmail.com
thank u sir
Sir,
I am getting Solver error - energy error too large.
What to do?
Please help me sir
Can u send me this file
am I the only one finding the incident velocity too high? at 1:00 the instructor says a velocity of 90000 mm/s that's 90 m/s which is 324 km/s !
brother 90m/s will be 0.09km/s or 324km/hr.
Hi
Plz sand me this file
Plz
How much time will it take sir? When I tried it is showing a hell lot of time
Solution time depends on mesh and defined end time
@@ANSYS-India I actually gave input as shown in the video. It took me almost 20 hours to complete. But the results depict only to crash, bouncing back simulation is not acquired.
In fact, I didn't get two curves crossing in energy summary
can you share the car body
what is the function of displacement ? sorry i am just beginner
+Adolf Ronny displacement is a boundary condition. Deformation is the function of load or displacement
How to calculate end time in explicit Dynamics ???
How to calculate end time in explicit dynamics analysis
woo amazing tutorial !!¿ do you know make the simulation of nanoindentation test? i need help in this for my thesis!
thanks !! good day
Sketch your problem description and email to engineeringtutorsdesk@gmail.com
how will it change if you do it for high speed crash like 30mph?
Greetings!! Paul, Analysis procedure will not change, you can observe the chqnge in the behaviour, stress, energy, and deformation.
Paul, For more Tutorial Videos Click on the link below
ANSYS Workbench
ruclips.net/p/PLOahOE6DpL4qq_QxPHieAeVejzDP1yIYW
ANSYS Multiphysics
ruclips.net/p/PLOahOE6DpL4qojPO7_GkgkVC-cB8KFMeC
Hypermesh
ruclips.net/p/PLOahOE6DpL4puVylWdpHWRoGhIfswDc6T
Creo Simulate | Pro Mechanica |
ruclips.net/p/PLOahOE6DpL4qvb2Z0Ir8SwvUyv0qnRGH4
Creo Parametric Tutorial
ruclips.net/p/PLC1voSxuLSym29Dt_xNnIJxBCtE-k9iul
Pro E Wildfire Tutorial
ruclips.net/p/PLLBsoJO8DYcVGLa_se2y5Ao0Vzwy6TUbz
For online training on ANSYS Workbench | Creo Parametric & Simulate | Pro E Wildfire & Mechanica | HyperMesh |
Contact: engineeringtutorsdesk@gmail.com
GRS CAD/CAE thank you
+GRS CAD/CAE Thanks for sharing the video. Great job ! Can you provide me the CAD MODEL of this tutorial ?
Sir I need to know why you took end time as 0.0007 second
I want to know the ground theory behind the end time
you can use formula speed = distance/time to get the end time by put your displacement
Hello, Please can you send me the CAD model of the car and the barrier
this doesnt look so good, why does de maximum deformation is in the back?
There’s a video in your ads
I owe you a beer
Cheers!! Here is the link for more videos ruclips.net/p/PLOahOE6DpL4qq_QxPHieAeVejzDP1yIYW
Could you please just change the way you talk!? You sound like a machine and it is so monotonic! Thanks