Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.
Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.
MEMS Cantilever Beam
Posted 1 juin 2012, 17:05 UTC−4 MEMS & Nanotechnology, MEMS & Piezoelectric Devices Version 4.0a 1 Reply
Please login with a confirmed email address before reporting spam
Hello COMSOL Community,
I am trying to simulate a very basic MEMS Cantilever beam. I simply want to see a deformation plot and and electrostatic plot. Once I figure this one out, I will move on to my actual MEMS Micro Mirror. But have to get this basic one down first.
I have the structural mechanics, moving mesh, and Electrostatics module used for this.
I am continually getting this error when solving a stationary:
Failed to evaluate variable.
- Variable: dnTEx_es
- Geometry: 1
- Boundary: 4
Failed to evaluate expression.
- Expression: d((mod1.smpn.d*(dnTEx_es*test(mod1.u)+dnTEy_es*test(mod1.v)))*(dvol),{test@1})
Could someone let me know what I've done wrong. Once I figure this, I can actually move to my own micro mirror, but since I'm fairly new, going past this hurdle is taking a lot of time. I've attached my model for your review.
-Dibya
I am trying to simulate a very basic MEMS Cantilever beam. I simply want to see a deformation plot and and electrostatic plot. Once I figure this one out, I will move on to my actual MEMS Micro Mirror. But have to get this basic one down first.
I have the structural mechanics, moving mesh, and Electrostatics module used for this.
I am continually getting this error when solving a stationary:
Failed to evaluate variable.
- Variable: dnTEx_es
- Geometry: 1
- Boundary: 4
Failed to evaluate expression.
- Expression: d((mod1.smpn.d*(dnTEx_es*test(mod1.u)+dnTEy_es*test(mod1.v)))*(dvol),{test@1})
Could someone let me know what I've done wrong. Once I figure this, I can actually move to my own micro mirror, but since I'm fairly new, going past this hurdle is taking a lot of time. I've attached my model for your review.
-Dibya
Attachments:
1 Reply Last Post 2 juin 2012, 03:54 UTC−4
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi
indeed I got a strange error message so something has got wrong in your model, anyhow v4.0 was not very stable in such cases, I would suggst that you remake the model from scratch
Anyhow I have a few other suggestions:
- for the ES force calculation, select only the canteliever domain "3"
- call the ES force variable only Fes (not the full name I beleive this is the confusion)
- add a Prescribed dispalcement on Bondaries 6 8 10 and use u,v respectively for the deformation
- change your domain "3" prescrived displacement to u,v and not "0,0"
- in the solid Force replace the User defined by the link to the ES in the drop down list, if it is not there use "es.Forcex_Fes" and "es.Forcey_Fes" variable names for x and y
currently your ALE is not drive by the "solid" deformation so you do not have a coupled model
The error message has something to do with the link of the ES force to the solid boundary load, but probably its your full "doted" name of the force in the ES Force calculation node, just use "Fes"
--
Good luck
Ivar
indeed I got a strange error message so something has got wrong in your model, anyhow v4.0 was not very stable in such cases, I would suggst that you remake the model from scratch
Anyhow I have a few other suggestions:
- for the ES force calculation, select only the canteliever domain "3"
- call the ES force variable only Fes (not the full name I beleive this is the confusion)
- add a Prescribed dispalcement on Bondaries 6 8 10 and use u,v respectively for the deformation
- change your domain "3" prescrived displacement to u,v and not "0,0"
- in the solid Force replace the User defined by the link to the ES in the drop down list, if it is not there use "es.Forcex_Fes" and "es.Forcey_Fes" variable names for x and y
currently your ALE is not drive by the "solid" deformation so you do not have a coupled model
The error message has something to do with the link of the ES force to the solid boundary load, but probably its your full "doted" name of the force in the ES Force calculation node, just use "Fes"
--
Good luck
Ivar