Stress Concentrations and Finite Element Analysis (FEA) | K Factors & Charts | SolidWorks Simulation
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- เผยแพร่เมื่อ 26 ก.ค. 2024
- LECTURE 27:
Playlist for ENGR220 (Statics & Mechanics of Materials):
• ENGR 220: Statics and ...
This lecture was recorded on November 6, 2019. All retainable rights are claimed by Michael Swanbom.
Please subscribe to my TH-cam channel and follow me on Twitter: @TheBom_PE
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I'm an engineer and this popped up in my recommendations. Don't know why I clicked but I watched the whole thing. I use solidworks this way pretty much every day, and I felt this was all perfectly explained. Wish I had a teacher like you!
I'm glad you liked it! Thanks for the positive review!
Hello, I am a graduate mechanical engineer and I work with SolidWorks. At the moment I am learning finite elements and I am enthusiastic about her lessons.
You are the best teacher.
Note at minute 56 onwards is probably one of the most valuable synthesized and elegant pieces of information that you could ever see in your career as an engineer. If he added some of st venant's principle it would have been absolutely perfect.
Very useful video.
Thats a great lecture :) I like the concept of basically asking your students to apply their best knowledge first, then show something which they would not have expected (so you have their full attention) and then showing them why is that and how it can be considered. Good job and thanks for sharing!
Thanks for the positive review! I'm glad you liked the presentation flow. All the best to you!
What a solid engineering professor taking somewhat random questions and clarifying them with ease. My professors could never
After wandering in the Solidworks / FEA desert for 15 years, I've finally stumbled my way up the mountain and in an hour the Guru has set me on the path to enlightenment. Been trying to understand this for years and now I feel -- not like I've got it all, but that I see where the path to getting it all lies and I can go as far as I need to get my work done. THANKS!
I was a notorious truant at school [back in the 80s], but hand-on-heart would never have missed one of your classes. I hope your students realise how lucky they are!
Spot on. Make sure to stay until the end where he discusses being able to ignore local stress concentrations for ductile materials
Thanks for sharing those great lectures so all students in the world can learn from them.
I'm glad you're finding them helpful! Thanks for watching!
You sir are amazing. Your lectures and real time examples have helped me understand better. This channel and your teaching is gold. Thanks a million and hope you get more subscribers.
I'm a engineer student and i found your channel for couple of weeks ago,i can surely do tell your channel and your wide expertise on mechanic area really taught me alot. i hoping for you the best.
Best Strength of material lecture i have ever seen.
Best Combination of Theoretical knowledge and industrial software .
You are very kind! I'm glad you liked it!
I am designing an aluminium chasis, I did some static structural tests on it, there were very localised stress concentrations. I was scratching my head for weeks to figure it out. This video cleared all the doubts.
Now I am confident that my design is pretty good. And those very localised stress zones will be fine.
Thank you very much.
It's such a great lecture.
Can't "stress" this enough, this lecture is great.
I studied electrical engineering at university and we had to study mechanical engineering for a year. I learned something more interesting about stresses from this video than from that whole year at university.
Great lecture , Thank you for the effort and way of explaining
I wish I knew about this before my FEA class… This is very helpful thank you. I wanted to note, at 29:00 when discussing curved surfaces causing element distortion with Solidworks you can apply mesh control locally to that surface instead of refining the mesh for the entire model(generally half the element size of the global mesh is standard). This will save you time and computer memory when running the mesh.
Good tip. I do the same. The way I choose on which bits to locally reduce the mesh size is to first run a coarse gobal mesh and then when I get the areas of stress I increase the resolution in those regions i.e. holes and other interfaces.
Watched this to get an idea about FEA before doing an assignment. This was really easy to understand. Thank you for sharing.
I'm glad you liked it! Thanks for watching!
Truly great lecture and a great way of presenting the material and knowledge, I am so glad that the youtube algorithm had led me to your lectures. I have already subscribed to learn more from you, hoping that you will also continue making such amazing insightful lecture videos. Keep up the good work sir :)
I'm switching over from creo to solid works and I been wanting to learn some of this on some of our mechanical designs. Great lecture and plan to use your knowledge. Thank you sir...
You're an incredible teacher. Thanks for sharing these for free
th-cam.com/video/IangXACFW48/w-d-xo.html
Awesome video! Thank you! Very great lecture sir!
Very good explanation, I must say, you are one of the greatest lecturer of all time, as you explain from the student point of view. I request you to provide some more lecturers on Solid works.
Thanks for the kind words, and thanks for the suggestion! I'll look at doing some more solidworks material!
This video helped me a lot. Great teacher, great explanations. Thx!
I'm glad I could help! Thanks for watching!
This was great! Much better than any of my college classes on this
Thank you for sharing these awesome lectures. Your lectures helping me a lot sir. I appreciate your passion to share your knowledge to whole world. once again thank you very much.
I'm glad I could help! Thanks for watching!
What a great lecture ! As a french person, it was very understandable, complete and not boring at all. I'm currently studying civil engineering, and have no need for solidworks, but I used to use it a few years back and I endee up watching the whole video even though I don't need it. That shows how interesting you made it. Wish all my classes could have been like that.
Just too bad you're using the imperial system and not the metric one, but no one's perfect I guess xD
Thanks for the positive review, in spite of the US units :D
Someday I'll do a brief video on why I present about half of my problems in US units and half in SI. Regardless, thanks for watching!
Thank you for sharing this kind of lecture easy to understand 👍🏼👍🏼👍🏼👍🏼
Thanks! I'm glad you liked it! In case you haven't seen them yet and might be interested, here are some of my playlists:
ENGR122 (Statics & Engr Econ Intros): th-cam.com/play/PL1IHA35xY5H52IKu6TVfFW-BDqAt_aZyg.html
ENGR220 (Statics & Mech of Mat): th-cam.com/play/PL1IHA35xY5H5sjfjibqn_XFFxk3-pFiaX.html
MEMT203 (Dynamics): th-cam.com/play/PL1IHA35xY5H6G64khh8fcNkjVJDGMqrHo.html
MEEN361 (Adv. Mech of Mat): th-cam.com/play/PL1IHA35xY5H5AJpRrM2lkF7Qu2WnbQLvS.html
MEEN462 (Machine Design): th-cam.com/play/PL1IHA35xY5H5KqySx6n09jaJLUukbvJvB.html
(MEEN 361 & 462 are taught from Shigley's Mechanical Engineering Design)
Thanks for watching!
Great lecture. This should be the future of education. I subscribed and activated the notification bell immediately. lol
Welcome aboard! Glad you liked it!
@@TheBomPE can you help me please,I have question
क
Many thanks for sharing, helped me out a lot!
I'm glad it helped! Thanks for watching!
Very helpful and comprehensive lecture on stress concentration , Thanks for sharing .
I'm glad you found it beneficial! Thanks for watching!
sir this was absoloutly great lecture thank you very much
Once again, a great video, well presented! I just want to note that the existence of the hole affects the stress in the fillet. That means that the hand calculation is not quite accurate and it explains the difference with the result in Solidworks.
Thank you for inviting me to your lecture.
I'm glad you joined in! Thanks for watching!
Very Informative video. Detailed explanation. Thanks a lot!
I'm glad you liked it! Thanks for watching!
perfect explanation, I followed very easy even being a Spanish speaker from Spain.
I'm glad you liked it! Thanks for watching!
Excellent lecture. Especially the last minutes were expanding horizon for me :)
Glad you liked it!
Thanks a lot! An amazing lecture :)
Glad you liked it! Thanks for watching!
I don't know why but (not knowing what the hell I'm looking at) I managed to guess what I would divide 5,000 lb.s by just by logical guessing. I know personally this means nothing but I'm proud of myself for following this with no prior knowledge
Your channel is a gem !
Thanks! I'm glad you are enjoying it!
@@TheBomPE I am ! Probably the best mechanical engineering lectures I have ever seen. Would love to have teachers like you at my uni.
Thanks for sharing. trying to learn how to apply FEA to large assembly models for things manufactured where I work. Been having trouble with the simulations getting errors during the meshing step. Have tried running on smaller sub-assemblies and still receiving errors. I can get this to run on single parts, but need to find out how to apply on assembly models to confirm that equipment will not fail for customers.
Great lecture. Really practical.
Thanks for the positive review! Glad you liked it, and thanks for watching!
Very well done!
Thanks! Glad you liked it!
Master Class!
Thanks! Glad you liked it!
Thanks for sharing this wonderful Video
I'm glad you liked it! Thanks for watching!
Very much useful and rich content
I'm glad you found it useful! If you haven't seen them already, you might want to check out a couple of my related playlists:
Statics & Mech. of Materials:
th-cam.com/play/PL1IHA35xY5H5sjfjibqn_XFFxk3-pFiaX.html
Advanced Mechanics of Materials:
th-cam.com/play/PL1IHA35xY5H5AJpRrM2lkF7Qu2WnbQLvS.html
Thanks for watching!
Perfect lecture ! Are you going to have also lectures about the theory of Finite Elements Method ? It would be great..
I'll keep that in mind as a potential lecture topic! Thanks for the support, and thanks for watching!
great explanation!
Glad it was helpful!
The amount of material above and below that one inch hole is equal to the narrowed 2 inch right side. If that 5000lbs. is the SWL, that's because it's the "Safe Work Load" for the least amount of material under stress
Thanks Sr. very good explanation.
I'm glad you liked it! Thanks for watching!
Thank you so much ...
Glad you liked it! Thanks for watching!
Lecture was very helpful.
Glad I could help! Thanks for watching!
thank you!
Glad it helped!
Thanks for sharing ❤️
Glad you liked it! Thanks for watching!
Thanks!
Thank YOU!
I wish I could afford an instructor like you
Could the difference in the reference on the book vs fem be due to the difference in distance from the boundary to the neck, presence of the circular opening or different boundary conditions regarding deformation parallel to the plane that supports the element?
wow importants aspects of mechanics explaned very well and shared on youtube good job SIR ! thanks a lot
so can i get the references used in this lecture like : reference material ?
Thank you! I'm glad you liked it! When I speak of "reference material" in this video, I'm referring to a document we have compiled that contains all of the required reference information used in this course. Mostly this document contains material found in our textbook for that course (Statics and Mechanics of Materials, 2nd ed. by Riley Sturges and Morris). Outside of this specific course, I would encourage engineers to search for the most relevant and up-to-date reference sources for their specific needs. Peterson is a good source for stress concentration factor charts.
Thanks for watching!
Great topic for a lecture….
Glad you liked it
Hi - thank you for making this lecture available. Should stress concentration factors be used for ductile materials?
There is a stress concentration whether or not the material is ductile, but as I discuss at around 56:40 and following, stress concentrations can often be safely neglected for ductile materials. Whether or not you should neglect them is controlled by whether you can tolerate tiny amounts of permanent deformation at the concentrated locations.
Thanks for watching!
TheBom_PE hey that clears it up, thanks. One last thing that has been confusing me - There was a question in Shigley textbook of the sheer stress in a double shearing pin. The solution didn’t use ‘sheer stress = V / A’ as I would expect but ‘sheer stress = 4V / 3A’ which is the formula for translational sheer stress in a round beam. I thought you would look for the sheer across the pin, not along the pin?
@@SeracS354
one is longitudinal shear stress and the other is transverse shear stress (from bending)
Classic explanation..
Thanks! I'm glad you liked it!
Excellent video and channel, was hoping for a swept brick mesh instead of those tets though!
Thanks! Maybe the next time I do an FEA video!
Hi. Thanks for sharing this. Aroud 47:30 you found slight differance between the FEA result and result you got from formula. The reason of that differance is that you used r=0.5 in in formula but 0.1 in in Solidwork. And ım suprised nobody in class told this to you :)
No. He did it correctly. The reason the stress values are so different is the effect of the hole in front of the reduction in part thickness.
In regards to this, I was also wondering why he used 0.5 rather 0.1 in the main formula when he changed it to 0.1 in solidworks specifically for the fillet. I understand 0.5 didn’t give any stress at the fillet location, which explains that 0.5 was a good choice to reduce stress. Did he purposely changing it to make it sharper to show stress, so the situation can be solved? The overall answer would be, don’t use anything less than 0.5.
thank you prof
You are welcome!
Great lecture and wonderful lecturer.
I can understand why you are using psi( American units) instead of S I (International) units N/mm2.
Now, it is clear from the results obtained from the analyses that the stress concentration is in the neighbourhood of the hole. Now, if the plate(say Steel) is used in building the deck of a ship and opening is provided for access, how can Solid work take care of reinforcing rings around the hole using triangular or other elements? Finally, are these lectures available as hard copy?
Thanks for the encouragement! In solid works you can model more complicated geometry and loading scenarios than what I did here. So if you want to investigate a reinforced hole in a ship deck, I would expect you could come up with some reasonable way to limit the bounds of your study to do that. I'm sorry, right now I don't have hard copies available for my lectures. Thanks for watching!
I would have been great engineering student if i had a lecturer like this 😔.
I'm glad you liked my lecturing! I'm sorry you had a less enjoyable experience previously.
great lecture, thankss. Whats the application you use for writing the solution?
I use Microsoft onenote 2007 (the last version with customizable toolbars). thanks for watching!
Hello. I downloaded almost all your videos and learned a lot of information thanks to you. In the analysis you made with the Solidworks program in this video, at minute 47:30, the r/D ratio should have been taken as 0.1/3 instead of 0.1/2 in the notch graph. A lower value emerged than the program's conclusion. With 0.1/3, the K value seems to be approximately 3.12, which gives a value of 15600 psi, which is quite close.
Thanks for the words of encouragement. The charts I'm using don't require the r/D ratio, only D/d and r/d. D is the larger width and d is the smaller width, based on the figure included on the chart. I believe the correct point was found on the correct curve in the video. Thanks for watching!
Great lecture! I have a question though. What if the problem is outside the bounds of the stress concentration factor graph? e.g. if the r/d value is greater than the range on the x axis of the graph. What are the implications of this and what should you do instead? Thanks!
If r/d is greater than the horizontal range of the chart, you have a few choices. (1) Look for a similar chart that has more range. (2) A conservative thing to do is use the K value at the rightmost point on the chart you have. (3) A non-conservative method is to roughly project the slope of the right end of the curve further right. (4) An even less conservative thing to do is ignore the stress concentration effect entirely since r is "large." (5) Occasionally you might be able to find or create an equation for the curve you are using which will enable you to more accurately project outside the curve's range.
If you go to the left of the curve's range, K is obviously increasing rapidly because the discontinuity is becoming sharp. At some point a plain stress concentration factor technique is insufficient, and a fuller, fracture-mechanics-based analysis is called for. If you are interested in a brief intro to fracture mechanics, check out these videos:
th-cam.com/video/SD6qITe3-Xo/w-d-xo.html
th-cam.com/video/E5tgDVN1zy4/w-d-xo.html
@@TheBomPE Thanks for the quick and detailed response! you've been a great help, I'll check out those videos
Amazing, still old-fashioned units of measurement but but at least in decimal system. :-)
Thanks for the kind words! I find that the abstraction of units systems conceptually occurs in the minds of students better when there are at least two units systems to deal with. If there is only one units system, we are at risk of inadvertently communicating to students that units are somehow transcendental, rather than arbitrary human constructions. Thanks for watching!
i had a simple question. there are charts and correlation for the plate when the whole is not there and charts and correlations when the fillets are not there .which to use?
Recommended
Thanks! Glad you liked it!
ok. so if i want to calculate stress concentration factor from the simulation, i have to divide the max stress from the color chart with the stress that is away from the hole and dont have the effect of the hole. and then compare what i got as a factor to the one from the charts for D/d ratios?
Think u doctor
I'm glad you liked it!
Which calculation is more accurate? One using the chart or one from FEA software(Assuming that you have the best FEA software available)?
Very informative video, Can I get the reference file somehow and a small question, Why can't we see the max principle stress in fem to compare with the analytical solution. Because the max principle stress will show Higher value. Basically I'm confused with whether should we use von misses or max principle stress to compare
Have a look on Mohr's theory and von misses theory, basically von misses includes the tensile/compressive stresses and transversal stresses (shear) and it's mostly used for failure cirteria for static ductile materials (if your allowed stress is lower than the highest value of von missed your component would start to yield. The principal stresses shows you the pure tensile or compressive stresses in your part.
As I mentioned above please refer to Mohr's circle and the description of the distortion energy by von misses to better understanding and application. Also have a look on failure criterias
we were using MATLAB to calculate this with massive tensors to solve. now it is easier hehe
You never changed the radius in the nominal stress of the filet when doing the hand calculation to compare with the results from SolidWorks
لااله الاالله محمد رسول الله
Excelente, what book do you use for the tables?
hello sir, Can you made a video with fatigue in case strain life ?? Thank you sir !!
It is one of the ones I would like to get to at some point! Right now my efforts are being pulled from making very many new videos to making better materials for online learning in the age of COVID. Hopefully sometime soon I can get back into making more new videos! Thanks for watching!
Hello Sir, do you have a dedicated playlist for FEA?
Never thought I’d need or want a Threadripper cpu. To bad they can’t make these programs utilize GPU’s. They are much better at parallel processing.
It’d be cool if they allowed to select areas and increase or decrease the mesh for just those parts.
I keep noticing very high concentrations in very small areas in the FEAs of various types of industrial threads. These stresses are in the thread root and contact areas. Typically it’s in the first three threads that the strain is highest. Do you have any advice on how one could mitigate or defend the results of an FEA with that type of result?
That's sounds pretty accurate tbf. Most of the stress will be on the first thread, then a bit on the next and a bit less on the next (something like 34%, 23%, 16%,11%,9%, 7% on each consecutive thread). If the bolt is softer it will spread more to further threads but yeah normally 3 threads are doing most of the work. For example in carbon steel you only need 1x the diameter in length of thread engagement to maximise sheer strength, so you aim for 1.5 to make sure you get at least a 1 times.
And yes stress is highest at the contact points of a thread, which you see when a thread strips. It makes sense when you think about it. The edges get rounded over. As for how I'd defend the results, well look at some pictures on the internet of stripped threads. That's how I check all my sanity check all FEA results. Do they match up with real world examples.
I don't know if you still check on this videos comments but I was wondering what software you use to write these notes. I just thought the function where you can move everything under a line down is so useful
I'm using Microsoft onenote 2007. That's still the best version of onenote from what I've experienced. Thanks for watching!
Hello. I'm a novice SW/FEA user who's beginning to work more and more with FEA for school. How do Solidworks' FEA simulations match up with other FEA software such as FEMAP or Nastran? When does SW not do an efficient job with finite element modeling?
Solid works in general is not that much used in FEA. ANSYS is a free software. The meshing quality is much higher with FEA dedicated softwares and will give you better results.
Student version of SOLID WORKS is available ?
I believe the overall load is 10K. You diagram shows 5K pulling from each end as opposed to a F that is equal and opposite.
No, 5000lb applied to one end with 5000lb reacting against it at the other end means that the part is carrying 5000lb.
hi what can i do if D/d IS NOT drawn on the chart for example D/d=1.75?
Thank you very much Sir it was a very good explanation, but what I did not manage to understand is that in this problem (in example) we have a concentric force applied in the cross section but when you used SolidWorks you did you use a distributed and non-concentrated force, why is that?
Cause it doesnt make a difference away from the edge
What is the name of this shape
can you please tell me difference in contact set and component contact in simulation.
Contact refers to how the components interact with each other (bonded, not bonded). The hierarchy in SW simulation goes as follows: Global contacts>Component contacts>contact set (local contact). Contact sets are defined between two faces/edges that can even be within the same component, these are commonly used in cases where you want to simulate interactions between faces that are free to come in contact but are also free to separate (no penetration contacts). When you choose component contacts SW requires a list of 2 or more components and it will impose the specified conditions on all faces it finds in common between those components. Because of their hierarchy, local contacts will overwrite component contacts and component contacts will overwrite global contact conditions.
Can you do a lecture on how to find the airspeed of an unladen swallow?
African or European?
Greetings young Tolar
Sorry maybe I didn't get it right, but in this example the point that you mentioned it won't yield 😅 at the end of the video
Should load not have been 10,000 LB's?
If we are given pressure load instead of that 5000 lb force. then what would be normal stress ? will it be the given pressure then?
In this video, I basically treat the force as if it is distributed uniformly on the face to which it is applied. This is equivalent to a pressure or stress, as you are asking. Thanks for watching!
@@TheBomPE means I don't need to find sigma nominal if a pressure is given as load in uniaxial problem like this. that pressure would be sigma nominal.
Correct... unless there is a different cross sectional area where you're calculating stress than the place where the load is applied.
@@TheBomPE yea thickness is same but the filleted flat plat is stepped.
Sir, how shall I contact you? I don't have an elder brother and whenever I've asked help from my seniors and faculties about my subjects, they just turned away. If possible please let me know.😔
bonsoir c'est les variations de température sur cette pièces et sa composition chimique usiner comme pour un moteur air bus de chez role roys sur ordinateur et soufflerie.
here is what Google translate gave me:
"good evening it is the temperature variations on this part and its chemical composition machined as for an air bus engine from role roys on computer and wind tunnel"
What is the application of this shape
th-cam.com/video/IangXACFW48/w-d-xo.html
What's the name of the program used and how to download it in Windows 10
D for depth
I'm not sure what you mean.