P-element method Vs. H-code for Pressure vessels
P-element method Vs. H-code for Pressure vessels
(OP)
P-element method Vs. H-code for Pressure vessels.
Is well known that for thin pressure vessel, most of the FEA studies performed are being done using H-codes as: Nastran, Cosmos and Ansys.
Now for thin vessels a minimum of 5 elements (please consider a simple “Solid” shell model) using Solid elements need to be placed across the wall.
Does anyone know about, how many P- “solid” elements need to be placed for a shell model… does anyone have a paper or reference comparing both methods?.
How well a “p-element” takes the stress gradient across a thin solid section?
Regards.
Is well known that for thin pressure vessel, most of the FEA studies performed are being done using H-codes as: Nastran, Cosmos and Ansys.
Now for thin vessels a minimum of 5 elements (please consider a simple “Solid” shell model) using Solid elements need to be placed across the wall.
Does anyone know about, how many P- “solid” elements need to be placed for a shell model… does anyone have a paper or reference comparing both methods?.
How well a “p-element” takes the stress gradient across a thin solid section?
Regards.





RE: P-element method Vs. H-code for Pressure vessels
Best regards,
Matthew Ian Loew
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
RE: P-element method Vs. H-code for Pressure vessels
higher).
RE: P-element method Vs. H-code for Pressure vessels
You may also be interested in the new interia relief feature, it's available in my video tip collection here
http://www.rmeng.com/index_files/page0005.html
Cheers mate
RE: P-element method Vs. H-code for Pressure vessels
RE: P-element method Vs. H-code for Pressure vessels
RE: P-element method Vs. H-code for Pressure vessels
A quick example, find the modal frequency of a square piece of sheetmetal. Pro/mechanica tends to create one or two shell elements only and converge nicely on a total crap answer.
I guess thats off topic, but what I'm saying about volume regions is that it never hurts to add a little h to your p.
RE: P-element method Vs. H-code for Pressure vessels
RE: P-element method Vs. H-code for Pressure vessels
As far as 'adding a little h', I agree, of course one should as much as possible take advantage of the advantages of each technique, extension of the number of elements or extension of the polynomial level. For regions of high stress gradients, such as notches or crack tips, it is unquestionably better practice to grade the mesh in the high stress gradient regions by increasing the number of elements. It is difficult with either element type, h or p, to get good results without taking into account what's really going on in the reality you are trying to model.