Can anyone please explain to me how and why in 2013 PATRAN does not have an undo button like virtually any other program for any other purpose one could think of. Yes I realise that it does in fact have an undo button but this can only undo the most recent action and not any before that, I mean...
That's great thanks for replying again! I'll look through the thread you linked and also at the examples of sources you gave. It's disappointing although not very surprising that there isn't a more regulated way of obtaining the data. Anyway, thanks again.
Thanks for the reply CoryPad.
I think the part which I'm struggling with is the fact that so many of the calculations in the document rely on input data such as prevailing torque, allowable applied torque, friction coefficients for the threads and underhead contact area and other such bits of...
Hi all,
On a project I'm working on I've been instructed that our first approach to determining the MoS values on the fasteners in a design wasn't correct and told to use the ECSS document on threaded fasteners (ECSS-E-HB-32-23A). I'm trying to implement the method in a spreadsheet now but...
I recently had similar difficulties in calculating thermal contact resistance values, it's a tricky problem and it seems like the most reliable way of determining values is from testing, especially when interstitial materials are used between two (or more) surfaces. However there is some useful...
Hi all,
I have the task of designing the casing of some electronics which are going to be exposed to a launch environment and so have to ensure that the casing can withstand the loads due to random and sinusoidal vibration as well as shock loading. I am a bit unclear as to how to go about...
Thanks again missil3. I ended up changing from my method of restraining the nodes and opted for yours of using BOUNDARY_PRESCRIBED_MOTION, it's much tidier way of doing it. Looks like you were correct about the revolving issue too, there doesn't seem to be a way of doing it in prepost which is...
Thanks for the reply missil3. The info I get from DYNA regarding the release is as follows:
"Version: LS-DYNA_971", "Version Date: 08/13/2007", "Revision: 7600.1224", "Feature: SMP Enabled". I am running DYNA on a limited license, one that is limited to 10,000 elements or less and I've been...
Hi all, another question regarding this project.
I've made a lot of progress with modeling the parachute, it now starts from a semi-inflated shape then collapses under gravity to allow for the fabric to fold and crease "pseudo-randomly" and then the pressure load is applied so it inflates and...
Thanks for the input everyone. I think I've eliminated a good few of the errors now, turned out a lot of it was to do with inconsistent units. I now have a running model which will hopefully be able to gradually debug. I'll post back on this with results or more problems, which ever I get...
Hi all, this is my first post so hopefully I'm not breaking some house-rules, apologies if I am somehow,
I'm new to using DYNA and am currently working on my first project which is to model a parachute. I'm modeling the post-inflation state of the parachute so really all I want to do for the...
