[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [PSUBS-MAILIST] FEA Work on Acrylic CT for KLH-500



Jon, I think that's a excellent plan. I was happy to have a real world destructive test to compare my original K-250 dome FEA work with. My results came out very close, and since I have a stronger dome model then the real deal, I suspect if I ran the data with a model of my dome, that came from a digital scan of the dome, I might be able to come even closer. I'm working on making a digital scanner currently.

I'm aware that my original dome could be a fair bit different then the one the Captain had destroyed. But on the other hand the might be really close to the same. It was just some data I could work on, to see if I was in the same ball park.

I've also been comparing my results to other FEA data on sub parts and assemblies I have found or been given. I know your plane flat viewport calculator is quite conservative, but I started out using that to compare my results some time ago. Now that I have better data on the material properties for Acrylite GP, Polycast, Plexiglas, and ASME PVHO-1 minimums and FEA skills, I'll run some more windows that fit the viewport calculator parameters, to see what we can learn. I know the CosmosWorks FEA software I'm using is able to do more advanced calculations. But I need to pull data from all sources I can at this point.

Cheers,
Brent

--------------------------------------------------
From: "Jon Wallace" <jonw@psubs.org>
Sent: Sunday, August 30, 2009 8:43 AM
To: <personal_submersibles@psubs.org>
Subject: Re: [PSUBS-MAILIST] FEA Work on Acrylic CT for KLH-500


Brent,

This is why I suggested doing some comparison tests against known data in Stachiw's book. Replicating the t/D data points of .045 that Stachiw recorded with actual testing (page 754) would give some credence that you've got the program configured correctly.

Jon

Today’s programs allow almost anyone to run FEA programs very easily but there has to be some deeper knowledge of the subject by the programmer to get answers that reflect reality. While your results look very professional, they can be misleading to those that do not know what to question (my knowledge and experience with FEA is rudimentary at best and I find issues). In the case of submarines if these persons act upon your published FEA solutions, it could be detrimental to their health. I respect all of the effort and research that you have put into your FEA work but would caution restraint in publishing your results.











************************************************************************
************************************************************************
************************************************************************
The personal submersibles mailing list complies with the US Federal
CAN-SPAM Act of 2003.  Your email address appears in our database
because either you, or someone you know, requested you receive messages
from our organization.

If you want to be removed from this mailing list simply click on the
link below or send a blank email message to:
	removeme-personal_submersibles@psubs.org

Removal of your email address from this mailing list occurs by an
automated process and should be complete within five minutes of
our server receiving your request.

PSUBS.ORG
PO Box 53
Weare, NH  03281
603-529-1100
************************************************************************
************************************************************************
************************************************************************