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DaveStupple
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Happy new year John. Salome is one of those packages that is very impressive in the training videos, but pretty non-intuitive when you come to use it. When it stops working deep into a project, it's soul-destroying.
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I can't see an Aster module. If it's in Tools menu, I can't access it as it won't drop down. I think there's probably something that could be done from the Python console, but I don't know what. I think I'm beaten on this occasion. I will see how mu…
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It gets better. The menus in Salome have largely stopped working. I get no dropdown with Controls, Tools etc. The dropdowns within the dialogue boxes no longer drop down, but I can still select with the mouse wheel. The save error brings up this k…
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Thanks Sergio. Martin, thanks also. Do you know how to find/remove the loaded MED file? I have no idea. I was worried about whether a second Salome instance would kill the first. Is it OK to start a second one?
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Thanks, you too.
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Oooh, (speaking from logic, rather than comprehensive knowledge now...) there must be some transference from phonons to electrons, otherwise - as I think you are saying - the barrier would be absolute. Whether the phonon transfers first to phonons i…
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This, by the way is why this feature is so useful. Yeah, it might be a shortcut to modelling thin layers, but it's also useful for these thermal barriers that have, effectively, close to zero thickness.
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Victor, yep, it is interesting. Diamond has a huge thermal conductivity, but - as an insulator - it is entirely through phonon (vibration) propagation, as opposed to metals, where free electrons are the main energy messengers. If the receiving medi…
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I've got a few papers on this where a thermal resistance at an interface is caused by a vibrational mismatch between the two materials rather than by poor contact or poor thermal conductivity of the materials. They vary in their naming: interface th…
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OK, that's good. Thanks Victor.
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Sergio, I've gmailed you.
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Sergio, thank you for that, that is an excellent tip. What a fantastic example of how to share an idea quickly and clearly with a simple sketch. We use the expression 'back of-an-envelope' (used to be fag packet, not so common now). Americans use 'b…
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Sergio, I am sure you are right. I have introduced a degree of partitioning to try to improve the discretization. I think maybe the transition from smaller to larger elements needs to be better managed. I can't share the geometry publicly but I will…
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Looks like Figure 1 of this (genuinely available from the Computer Graphics journal website).
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Set the analysis type to Thermal steady state or Thermal Transient. You can select the relevant faces then apply a Convection load (Right click selected faces, Loads & constraints>New convection) typically in W/(m^2.K). Typical values here.
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Thanks Victor.
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A neat trick, I hadn't thought of that. Yes, I'm just visualizing basic textbook concepts. Would I be right in saying that in a simple system like this with uniform loads the principal planes (if I'm using the right term) would be in the same orient…
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Changing to a non-linear static 3D analysis and ticking CCX and quasi-static makes the displacement vary correctly with time, but you are limited to certain cross sections.
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There are some red entries in your model tree, and also in the displacement (10xt) the t variable is in red. It looks like t is not an acceptable variable for an equation in dynamic response. I don't have a solution for you, but I think you need to …
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With the initial time step at 0.1 s the solution failed to buckle: when I changed it to 0.01 s the solution looked like Victor's.
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Thanks Victor, I'll take a look at the dreaded CCX manual. Prop design, I know not much about Salome. I have it installed and have had a go, but I found it quite confusing. I believe it does do hex dominant. It looks like a useful tool. These love…
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Works fine now. I was confused that the resistor button was not available, but I just used the conductivity property. Applied this to a trivial problem of filament temperatures, mainly because I wanted to see if I could make the helical mesh. It wou…
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Some great ideas to play with, thanks everyone. If I create anything interesting I'll post it.
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Thanks Disla and SnuggleKittens for the two examples - just the sort of experiments I had in mind.
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I'll have to think on that. But thanks for the clarification. Maybe that is why I got the silly stretching in my early attempts.
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Your two points make perfect sense - the first one is less obvious to me than the second one (should have been!). I managed to get one swinging last night, but I can't get any to solve today. If I uncheck Automatic Time Steps the solver gives up wit…
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Victor & JohnM, thanks for that.
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JohnM, would the dummy thermal be run as thermal steady state using the internal solver? After this, transfer temperatures from solution to create a set of node temperatures. How to go from here to temperature dependent E? Do we need to switch to St…
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I haven't used STEP files much, but when you right-click your step file in the tree there is a Meshing Parameters option. In here you can ask for a finer mesh etc. which might help. The option for surface mesh is also here.
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OK, that didn't help. CCX can be very daunting, but if you are lucky Mecway takes care of everything and it all gets done behind the scenes. The first couple of warnings might be addressed by selecting Quasi-static and then put in a duration and tim…
