Good Day SolidWorkers,
I am doing a pressure vessel analysis, based on what I have taken from the training material. Fortunately the design is to the same code, ASME Boiler & Pressure Vessel Code, Sectio VIII, Division 2.
My question is, how do I analyze the SECONDARY MEMBRANE, as the training material only covers post-processing the primary membrane stresses and I can't find anything online or in the help file.
Any assistance would be greatly appreciated.
Kind regards,
This can be rather tricky to do and is an issue with trying to use FEA results (i.e. a continuous stress field) with standardized design codes. My (limited) understanding is that there is no direct and formally accepted method, but there some potential solutions.
Your FEA analysis calculated the total stress across the domain, but to use these results with the ASME code, you'll need to decompose this total stress value into the primary and secondary stress components, which you might be able to do by:
Thanks for your responses gentleman.
Jared, I was referring to the ASME Boiler & PRessure Vessel Code, Section VII, Div 2. There is a value "Q" which is supposed to be the secondary membrane stress. I was just wondering if there was a simple way to view this in a pressure vessel analysis.
Bases on Shaun's response, it seems that there is not, but thank you Shaun for the advice.
find out what Q is and then i can give some suggestions on how to pull the information out of simulation
Hi Jared,
As per the code, the definition of "Q" is as follows:
Self-equilibrating stress necessary to satisfy continuity of structure. Occurs at structural discontinuities. Can be caused by mechanical load or by differential thermal expansion. Excludes local stress concentrations.
Thanks for the assitance!
good definition, how is it calculated? if you were going to do it "the hard way"
I was pretty much going to figure that out as I went along!
Would be my first time doing it, both analytically and computationally.
It's not too urgent, it's on the backburner for now.
please define "secondary membrane" or link to a reference
SWX is WYSIWYG, so if you can't find it, you may need to pull data and do it yourself