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Hi

Well my opinion is clear COMSOL is the best physics study tool you can get today, and by far for detailed FEM analysis in multiphysics domans.
And what I assume is behind your studies is multiphysics, with "solid" structral, probably some touches of PZT or piezoresistivity, and why not some thermal aspects. This can be mostly covered by the MEMS module, perhaps too with structural ant thermal modules, while if you use electrstatic devices such as capacitive sensors the the ACDC module could probably be also of interest.
Not to forget some CAD tool. An external one is of no obligation as the CAD tool inside COMSOL is quite powerfull, still not a true "mechanics design tool" but certainly a good tool for even complex FEM geometry

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Good luck
Ivar

sir,
thank you for your valuable opinion.
Hereby attach my base paper of my project and its how to implement and working with help of comsol software..

Hi

you have a nice but complex model if you want to take int account everything here, indeed MEMS module should do the essential, else ALE, Solid and ES could probably be a first start combination if you do not have MEMS, but thin film air/gas damping efects, requires the MEMS module

My first recommendation: start simple go one step at the time with one physics (solid) first then complexify, and save the intermediate states.
Your challenges will certainly be around the generation and meshing of the comb capacitors, then for the physics, with MEMS you have often shart edges and vertexes (depending on manufacturing technology, whet etching is delicate, as you need to remove all silver edges the crystalline Si gives you, else your parts transforms to "advanced high tech sand" before you get the wafer out of your liquids ;)

The resulting sharp edges generate huge stress concentration effects, that are not easy to cope with, here some reasonnble engineering assumptions must be made on the true radius of curvature to be used on the flexing parts and their attachment. Not to say mesh density to reolve the steep gradients.

If you use other atacking methods, thereare a few, you might have rounded edges, but you need to get rid of the scalopping, by adequate tratments, and such surface finish is also difficult to get representative. You can in fact just start with an "L" braket and study that for some time, and make it really representative of the electron microscope images you can get from the manufactued device. Or you ignore these details on go for the system ;)

Really anough to go for, a nice project

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Good luck
Ivar

Thank you sir,

Hai,

I already send my project abstract to you and your reply was useful to me.I know about some application oriented ideas relevent to my title.

I create comb capacitor and substrate in seperate files,How i merging the two models in same model in comsol software to complete full model.

Hai sir,

i want to remove boundary lines between the two blocks in torque sensor.what are the steps should be follow.
Version:comsol 4.2a

Hi

have you checked the union and convert to solid and dechecking the "keep interiour boundaries"
But in general internal boundaries are not any nuisance, often very useful for postprocessing or for mesh creation

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Good luck
Ivar