Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations SDETERS on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  • Users: sushi75
  • Content: Threads
  • Order by date
  1. sushi75

    Fatigue and crack propagation life

    Hello! I'm a bit puzzled about fatigue and crack propagation. Given a SN curve, this one will predict for a specific level of stress what number of cycles are required to FAILURE, let's say 10e6 cycles. Assuming an initial flaw of 1mm, and using Paris' law, a crack propagation analysis by...
  2. sushi75

    Stiffness of shell vs plate

    Hello! I try to understand why a shell is stiffer than a plate. I've read a note on the internet explaining that moving a point out of the surface of a thin shell like an egg takes more energy as the adjacent fibers have to be stretched, unlike a plate. But it does not make much sense, and I...
  3. sushi75

    Ti-6Al-4V Heat Treatment

    Hello! I'm currently working on a structure made of Titanium, Ti-6Al-4V, and it is heat treated to improve mechanical properties. So I''ve been through a lot of books, documents, internet to get a better understanding of the heat treatments, and now I'm a bit confused. So I need some help to...
  4. sushi75

    Modelling a weld

    Hello! I would like to assess the stress level at the location of a weld. Basically this is a tube into a solid; so the interface will be the surface contact which is a cylinder in that case. I'm aware that there is a connector menu in femap which has the option of weld, but i don't think I...
  5. sushi75

    Yield Criteria

    Hello! I'm running a FE stress analysis, and checking the maximum Von Mises stresses, the values remain under the yield strength. However, looking at the maximum principal stress, there are values above the Yield Strength. So I'm a bit puzzled, according to VM there will be no yielding but...
  6. sushi75

    Buckling Imperfection Factor

    Hello, I've started a thread in another forum, but following advice of one of the member I post it here as my analysis is applicable to a pressure vessel. So here is the summary of the problem, hope someone can give me guidances and good information to progress!! Thanks! I'm currently going...
  7. sushi75

    Sine Environment

    Hi all, I'm going through dynamic analysis, and I've got a simple question: why is it so important to have the structure outside the sine environment?? If the first natural frequency is outside this range, let's say above 100 Hz, it doesn't mean that it will not be met. Hope someone can...
  8. sushi75

    Buckling Imperfection Factor

    Hello! I'm currently going through buckling analysis, for a hemispheric shell. So it a basically a portion of a sphere. It is subjected to a pressure load on the external surface, therefore it can buckle. From handbooks I could calculate the thickness, radius and angle using handcalcs. But I...
  9. sushi75

    Crack Propagation

    Hello all! I'm working on crack propagation, and I have a few question about propagation. From my understanding, fatigue will iniate a crack along the shear plane (so 45 degrees for tensile loading). Then a crack will propagate perpendicular to the loading. Then stress intensity factor is...
  10. sushi75

    Post Processing and Corner Data

    Hello! I have a question about post processing a model. It seems that regarding what option we chose, the results are very different, at least the contour looks different. What I don't understand also is that there seems to be a sort of stress concentration at the location of the geometric...
  11. sushi75

    Mesh Size

    It's quite convenient using the meshing toolbox to modify the mesh size on curves, in order to have a better mesh. But that's a bit of the problem, the choice of the number of elements chosen is sometimes a bit random, until it becomes regular. I'm working on a solid model with tet10, and I try...
  12. sushi75

    Interpretation of buckling results

    Hello! I'm running a linear buckling analysis of a curved shell submitted to pressure load. I would like to check if there is snap through. It is pinned all around the edges. Looking at the first mode shape, it looks like a snap through shape, so if the buckling factor is lower than 1 means...
  13. sushi75

    Best Practice - FEA Methodology

    Hi Everybody, I've been working now for a few months on FEA, and what I found sometimes difficult on top of the analysis itself is the way I organise the files and the work. It's usually required to modify the design, or the mesh, try different load cases, or analysis type etc etc. So from a...
  14. sushi75

    Enforced Displacements

    Hi Everyone! I'm facing a bit of a challenge that I would like to share with you. I need to apply enforced displacements on many nodes (nearly 1000), I manage to isolate them in a group, and the value of the displacement to apply is a factor times the node coordinate. So the issue is: how do...
  15. sushi75

    Output CS

    Hi All! I'm trying to get my head clear with the output I get, in particular the displacements. Is there a way in Femap to visualize what the output coordinate looks like? I've got a model defined in Cylindrical CS, and output in Cylindrical. But is this output CS defined relative to the...
  16. sushi75

    Modelling pressurized cylinder

    Hello everyone, I try to model a cylinder of internal radius a and external one b. The structure is submitted to a radial pressure p. The cylinder is opened on both ends. From books, there is a radial and hoop stresses, but the z-stress is equal to zero. I don't understand this point as I...
  17. sushi75

    Results with SOL106

    Hi everybody! I've got a question about results I obtain from SOL101 and SOL106, which are massively different, so I wonder which one is the most accurate. The analysis is a pressurized plate, pinned at both ends. Linear Static analysis predicts a pretty large deflection, and a high max...
  18. sushi75

    Unzip Nodes

    Hello! I have a question regarding the unzip command on Femap. I have tried it on a simple example, shown attached which is a flat plate fixed on one end and pulled on the other one. I have unzipped 2 nodes, with connection type set to None. This creates duplicate nodes, but the mesh remains...
  19. sushi75

    Glue Contact

    Hello, I have a solid geometry that I would need to include in an existing model mesh with solid elements. As it required to connect TET and HEX, it seems that the best option is to create a glue connexion between those solids. I'm not familiar with this femap capability, so I'm trying on a...
  20. sushi75

    Linear and Non-linear Buckling

    Hello everybody, I've have to deal with stability which requires a buckling analysis. Howevert, I don't really have a clear idea of the difference between linear and non linear buckling! What's the difference, and/or how can we decide wether or not it's linear or non linear? thanks a lot for...

Part and Inventory Search