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Hi

but you have many empty nodes in there and a double solver sequence. First rule: always clean up your model, ideally by deleting all unused / undefined nodes (minimum disable them) then regularly do a : Edit clear all solutions clear all mesh File reset history and save (with an increase minor revision number:
NOTE: this destroys your results and the latter the history and back tracking capability

Often, if you have played a lot with your solver settings its also worth to delete the solver sequence and restart from scratch. This proposes to delete also ALL related plot and results nodes, annoying if you have done a lot of Results work, but keeping old things, which now is possible (Thanks COMSOL developers ;) might also give you headaches how to knit them back to the new results.

Learn the COMSOL way:
when you delete a node higher up, all related nodes lower down in the tree (in depth and down => 2 direction) are deleted !

once cleaned up it will probably solve nicely ;)

One thing, once you have it running, consider to make the mesh somewhat finer the eigenfrequency might be more precise

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Good luck
Ivar

Thanks Ivar, my problem now is when i use a fine tetrahedral meshing i get an out of memory error. and when i use a coarse meshing the solution does not converge. what can i do to the geometry to solve both problems? i am using the book "Multi physics modelling using COMSOL a first principles approach" by R. Pryor and it seems to be related to an older version of COMSOL. Is there any text you would suggest for 4.3a? I am a new user with community college level education so i am unfamiliar with the differential equations i see being mentioned in the forum and in the book i am reading. I use the models online but there is not enough explanations as to what the steps are for so that i can re-use them in another model. I have attached the revised model.

Hi

note that "prescribed displacement all =0" and "fixed" are the same BC.
Furthermore, your force is not set correctly, as you have selected force per surface (pressure) so you have an orange "unit error for a force defined in Newtons

If you have a RAM issue with fine mesh, you could consider to solve only 1/4 as you have a symmetric case here

On my WS (with plenty of RAM) it solves OK, and stating 1.25Gb of ram


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Good luck
Ivar

The geometry worked well, Thanks Ivar. i am trying to add a vibrating load to the same object but it is not working, i used some of the vibrating parameters from a rock blasting comsol built in model but the solver says it does not converge. How can i find information on these steps. i am attaching the model so u can see what i have done.