I'm trying to work through a thought experiment with a colleague about how to estimate the heat transfer across a riveted joint. The application will be in a vacuum, so there's no interstitial fluid between the joined members to help with conduction. Thus you are highly reliant on surface finish...
I'm trying to work through a thought experiment with a colleague about how to estimate the heat transfer across a riveted joint. The application will be in a vacuum, so there's no interstitial fluid between the joined members to help with conduction. Thus you are highly reliant on surface finish...
I have been looking at a high-performance thermal pad to use on the heatsinks for several high power dissipation components. The thermal pad is relatively stiff and requires a certain level of compression in order to achieve good levels of thermal conductivity though. I'm concerned that the...
For starting I context, I have a FEM with 2 primary submodels that are broken out into separate include files. Each of the two parts runs without issue on their own (free-free modes, fixed modes, and random vibe cases). When running together the two parts are connected by a ring of CBEAMS...
I am creating some vibration test specifications for a customer and using the methodology described on https://femci.gsfc.nasa.gov/random/randomtestspec.html. I’ve been using the FEMCI “book” as a resource for my work in the aerospace industry for years, and found that many consider it in itself...
I want to track the accelerations for the CG of my spacecraft from frequency response analysis runs. This is is obviously not a physical point in the FEM though. I'm thinking an MPC of some sort is the approach to use, but unsure of the most accurate way to implement it. The simplest (as far as...
I have encountered an odd issue while doing geometry prep using some of the cleanup and editing features in the meshing toolbox. Part way through creating my model I suddenly cannot select anything when using options from the Feature Removal or Geometry Editing sections. For example I want to...
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This was a very useful discussion, but unfortunately (as is the nature of all things centered around computing technology) I think most if not all of the conclusions are now out of date. For example I believe the ILP-64 solver is now the default in newer versions of Nastran...
I have a model which has a significant number of high frequency modes >300Hz. For example between 300Hz and 500Hz there are almost 160 modes alone. My excitation environments run out to 2000Hz, however. The runs are taking an inordinate amount of time as a result unless I only include a subset...
I'm trying to run a dynamic reduction within FEMAP, but am having issues getting it to produce the expected output files. My goal is to get mass, stiffness, and damping matrices as well as data recovery matrices (ATM and LTM) all in OP4 format. When I run the analysis within FEMAP it completes...
I am working on designing a thermal control system for an array of telescopes that need to be kept at very cold temperatures, and within a very tight tolerance. Constant conductance heat pipes are being used to bus waste heat from the telescope detectors to a deep space radiator. Each detector...
I received a random selection of analysis files from a recently departed colleague and I am trying to play forensic scientist to uncover what that status of the analysis was. Most of the analysis was done in Nastran which I have had no issues accessing in FEMAP. Some of the models were run in...
I am trying to run a plane strain model that has several components which do not have isotropic properties. They are made from composite layups, but I have calculated equivalent orthopedic properties for the layup schedule. Now I have a plane strain model of a different section of this assembly...
I am trying to run a plane strain model that has several components which do not have isotropic properties. They are made from composite layups, but I have calculated equivalent orthopedic properties for the layup schedule. These numbers worked fine when I was running a solid model with MAT11. I...
I'm modeling a turbopump system that has pressures applied to the inner surfaces of the FEM. The pressures are from an external source and I have mapped them as imported data in Workbench. I am doing a nonlinear static analysis and have the pressure being applied gradually (nothing fancy, just...
Most of the analysis I do currently is in NASTRAN. I am very familiar with that code's paradigms and associated tools for model creation, but recently have started getting work that requires ANSYS. I have become a little spoiled, for lack of a better word, by tools like HyperMesh and FEMAP which...
Most of the analysis I do currently is in NASTRAN. I am very familiar with that code's paradigms and associated tools for model creation, but recently have started getting work that requires ANSYS. I have become a little spoiled, for lack of a better word, by tools like HyperMesh and FEMAP which...
I have been trying to debug a model that has been giving me some issues for the past couple days and so far have not come up with any solutions. The model is reasonably large (~400-500 MB) and involves some fairly complicated connections between components in order to release specific DOF at...
I'm using 1D COMBIN14 elements to connect coincident nodes and manually control the stiffness between them for each DOF. The orientation for each spring is based off the nodal coordinate systems of the nodes defining it according to the ANSYS manual. I want to know the forces between these two...
There are several threads about importing geometry from classic ANSYS to Workbench, but is it possible to import the FE model (i.e. mesh, materials, constraints, etc.)? Using the CDWRITE command you can get separate geometry (.iges) and FE data file (.cdb), and it's pretty straight forward to...
