![]() ![]() ![]() Then, I write the expressions and variables. I use swept meshes quite a bit, and they help a lot in this process - since they can get rather vocal whenever they hit even a small inconsistency. My first step is always to check the dimensions and "fit" of the model, especially if I import geometry. Now I'm finally ready to solve, analyse my results and to validate my model. more for specific needs, but let’s stop here, just now, and get your feedback. I solve and check the stress build-up, there should be none if my model is correctly constrained. 1.2E-5, then in the "Load" tab I set include thermal expansion and put 100☌ temperature difference between "Temp" and "Tempref". Upd: 6) Static load check: by applying an acceleration of 1m/s^2 in x,y,z one should get reaction forces corresponding to the total mass of the model.ħ) required for thermal analysis, but I mostly do it systematically: I go to the Subdomain Settings, I select all subdomains and set the thermal expansion to the same value i.e. ![]() My tolerance here is typically 6 modes, none should be close to 0 Hz (typically none <1Hz if I expect my model to be fully constrained in 3D)īy the way, an additional question: how many modes to consider, how to, in COMSOL without any mass participation factors available, should one decide that most relevant modes stop at X Hz or after N modes ? domains and do not forget any masses added to specific "points", if applicable). "rho_all" and set it (Options Expressions Subdomain Expressions) and give the specific densities for the different subdomains, respectively shell, beam. Upd: 0) I import generally my CAD geometries from SolidWorks or another CAD tool to have independent volume, mass, centre of gravity (CoG) and inertia tensor calculations.ġ) set up the model, the BC's, the material etc, mesh it and solve for "Get Initial Values" (just to fill the matrices).Ģ) check the mass against my CAD model values by: "Postprocessing Subdomain Integration" insert the density expression "rho_smsld" (or whatever application mode you use, but if you have several you must make a global variable i.e. The COMSOL documentation talks about how to do multiphysics for the Scientists, I'm still searching the specific chapter(s) on model verification methodology for us Engineers ) Thereafter, I "validate" my model that is: I compare my solved model results with my measurements to check that my "validated and solved model" is truly representative of my existing device being modelled. I start with this even before I solve the model. not overlooking something, then only you might "solve" and validate your model against your measurements.ĭefinitions: for me "verification" of the model is checking that I'm coherent with the physics and I'm respecting the global hypothesis and limitations of the application mode. I'm interesting to know and to exchange means how you verify and validate your structural models, how are you sure that the model is set up correctly?Īspects such as: no over-constrained BC's, you are asking for sufficient many modes, i.e. First, I would suggest that we all start our subject line with a short summary of the application mode and the version we use or to which we relate our discussion, this would help us others to sort things and to give better replies.Įither by mentioning the specific application mode i.e, or at least the global title in the subject line, knowing that the more precise we are more and better replies we could expect.īack to my specific question, (by the way Niklas I'm sure you are out here reading our comments, this could also be a subject for your Blog) : ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |