opinions on using Comsol?

[biff44]

Anyone been using Comsol for a while? I have an application where I need to model microwave antennas and cavities for heating liquids, and it seems to be exactly designed to do such a thing. It also seems to be much more affordable than CST or HFSS.

Good software? Accurate results? Easy to learn?

 

[Hash]

COMSOL is a good software with which you can tune a lot of things (really). I like to say that HFSS and CST are engineer softwares (not so much options in numerical solving for example), while COMSOL is more a physicist soft... Which mean that there is a lot of things to learn, and the soft will not so much decides the parameters for you. For example, when using the RF module, the meshing is generally not fine enough...

Anyway, the RF module is OK for two ports devices. When you go to higher number of ports, you may have some trouble if you want the full S-parameters matrix... The problem has been solved in the very last version, but since, getting and reading the S parameters is simplet with HFSS or CST.

 

[biff44]

Thanks for the reply. I was looking at the multiphysics aspect of comsol, where for instance I could have a small volume of liquid and move around antenna elements to see what temperature the liquid rises to after application of 30 watts for a minute. Comsol will let me include coductive and convective heat losses, etc.

Can HFSS or CST do that? I know they can accurately compute Efields, but power transfer to a media and the temperature rise?

I do have access to CST, but am not up on its details.

I was primarily thinking of Comsol because it is 3 time cheaper than cst, and 6 times cheaper than HFSS. Man, why do these emag companies charge so much. An independent consultant simply can not afford those astronomical prices.

 

[Hash]

I was looking at the multiphysics aspect of comsol, where for instance I could have a small volume of liquid and move around antenna elements to see what temperature the liquid rises to after application of 30 watts for a minute. Comsol will let me include coductive and convective heat losses, etc.

Yes, for sure. Is there a flow in the liquid or not ? If not, it's a simple electromagnetic-then-transient-thermal simulation. If there is a flow, it is more complicated since it may required some fluid calculation (flow, heat echange, etc.) .

Can HFSS or CST do that? I know they can accurately compute Efields, but power transfer to a media and the temperature rise?

Yes they can.

In particular HFSS (Version>13), which can easily be coupled to the last version of ANSYS Workbench (Version>13). Then, using ANSYS, you call HFSS to calculate the heat source inside your lossy material, which is then used in an ANSYS transient analysis.

CST a thermal solver embedded, for simple thermal modeling.

I was primarily thinking of Comsol because it is 3 time cheaper than cst, and 6 times cheaper than HFSS.

COMSOL is maybe cheap as a standalone product, but it's price really increase when you add modules (for instance, the RF module you require for your application, or the heat module which may help you either...)

Best regards,

 

[vpp]

hi everyone

i m working on comsol and new to this . i drawn my geometry for microelectrodes but dont know how to apply ac signal to one of the electrode. i m using electrostatics in AC/DC module.if want to see my model i ll send .
plz help me