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Hi, Are the two radii the same? It might be possible to improve the understanding of what's happening by changing the rads (while keeping them the same as each other). Also, if possible, maybe review the convergence performance, error estimates etc to see what the solver's own estimate of the...

Hi, I tend to use Abaqus or Nastran but requirements can be pretty similar - 2GHz+, 4Gb RAM, 100Gb memory seem to failry standard minimum levels these days. One trick that helps me is keeping the hard disk reasonably clear and defragmented - if the program can write its temporary files in one...

Hi, Have you tried the Abaqus forum, their hotline or the Status Report Search for bugs (on their website)? Alternatively, maybe search your drive for df.exe and copy it to where you're running... Also, LOADS of 6.4 bugs seem to be fixed in 6.5. Good luck!

Some of the Abaqus courses can be quite generic (especially the earlier parts). DAMT also give general training.

Hi, The NAFEMS Analysis Management Working Group has recently been looking at the following ASME definitions (re ProbaSci's comments on Modelling/Numerical checking): Verification ========= The process of determining that a model implementation accurately represents the developer's conceptual...

Hi, If you can't refine the slave, can you coarsen the master? The meshes should ideally remain fairly well-matched. Also, are you using penalty or kinematic contact? (Maybe try the other one!) If the penetrating nodes are midside ones, can you try Abaqus 6.5? This seems to help a bit. Is it...

Hi, You might find this answered better in textbooks eg Huebner & Thornton, or just Googling for lecture notes that go through the detail. On the other hand, it's simpler just to evaluate everything at Gauss points for consistency. Some smarter codes I think evaluate M and Fint at the nodes...

Hi, If you're using PDL code then is your front-end Patran? The simplest route may depend on the solver too, eg if it's Abaqus then you can create a function (specifying the spatial variation, eg as a table) and then pick this function when applying your temperature over the area. Other codes...

The short answer is no, I don't think ProMech can handle non-linear materials directly. However, it might be possible to approximate overall average behaviour with a sort of "lumped-parameter" model eg if the average cookie region has 5% porosity then reduce the stiffness, density and strength...

Adib Becker at Nottingham University, UK, has done a lot of work (inluding with NAFEMS) on weld modelling, tho usually for stresses rather than distortion - maybe have a look at his web pages/Google, ring or email him; I regard him as a bit of a weld modelling "guru" (in as much as anyone...

Hi, I don't think ProMechanica can do this directly, especially not if there's significant sliding/friction. In Nastran we wrote macros to create the necessary array of springs (for a slightly different purpose!). However, the contact pressure might indicate the sort of problem I guess you're...

Hi, The spring constants should come from the element area and spring length ie stiffness = modulus * area / length. If this initial model treats the soil as linear, it's worth checking the soil strain (from displacement) to see if there's a risk of non-linear behaviour (depending on whether the...

Hi, I generally reckon that a minimum accuracy level is with two Gauss points within 10% of each other at the stress peak (eg 300 and 330MPa) - ideally agreeing to within 1% (or 2 significant figures eg 300 and 304MPa). In these cases the element averaged ("contour") value should be pretty close...

I've used Caesar for pipework but seen Finglow used specifically for pressure vessels (you can hire it) - we used to treat pipework terminations as constraints in Caesar then impose the loads and moments on the vessel model in Finglow. Done some work assessing old pipework and associated plant...

It may be worth checking what pre- and standard-memory are set to in the abaqus.env file, which tells Abaqus how much RAM to use for each job in the directory containing the ENV file. Setting this to 100% RAM can run the risk of "Code 5" crashes if Abaqus then conflicts with Windows...

My understanding is that ProMech contact is frictionless - this may not matter in your application if the assembly is well-lubricated or contatc is mainly normal, with negligible sliding, but otherwise it can give significantly nonconservative results so should be used with caution... Good luck!

Hi! While Abaqus does have some specific fracture-related features for grey iron, it may be enough to just input the stress-strain curves point-by-point; authors such as Angus and Roark regard the material as non-linear past about 25% UTS and some tests I've carried out confirm this (others with...

Hi, As I found Bannantine quite hard to get hold of, here's my take on these parameters: A strain-life curve is basically made up of two log-log straight curves for the elastic and plastic strains; elastic coefficient = fatigue strength coefficient elastic exponent = " " (Basquin)...

Hi, Depending on your location and industry, a German university (Paderborn?) produces Hexagon software which can help design some bolted joints. For simpler hand calculation some application standards like BS5500 on pressure vessels contain some quite extensive bolt calculation sections which...

It might help to get some idea of the defect size and number. Two possibilities are: 1) Model the casting process with software like Magma 2) Measure and count defects post-manufacture with non-destructive testing or by cutting slices You could then maybe take some account of their effect by...