×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

transducer problem

transducer problem

transducer problem

(OP)
Hi
I'm trying to simulate a membrane under an electrostatic field using transducers. If i generate transducer elements for each node of the membrane in one step, it works good (the results correspond to the theoretical equation).

Now I'm trying to generate two levels of transducers. I generated transducers correctly but results were not correct. So I generated transducers in two steps but the distance between was the same. It should give the same result like in first simulation but it wasn't. (membrane's deflection (Z displacement): 1 level - 0.0612, 2 level 0.052) Increasing number of levels gives bigger difference (ex. 9 levels - 0.216). Where is the problem?

Here are the scripts:

----------------------------------------------------------
transducers in one step
----------------------------------------------------------

FINISH
/CLEAR
/CWD,'C:\temp\ansys'

!* membrane
Lm=300
Wm=300
Tm=5
!* membrane_division
b=30
!* electrode_distance
h1=-0.3

dif=20

!*dimension de l'electrode
a2=75/Lm

!* voltage
v=20

/PREP7

   ET,1,SHELL93
   R,1,Tm

   ET,2,TRANS126

   MP,EX,1,130e+9*1e-6
   MP,DENS,1,2330*1e-18
   MP,PRXY,1,0.278

   WPOFFS,0,0,dif
   RECTNG,0,Lm,0,Wm
   WPOFFS,0,0,-dif

   LESIZE,ALL,,,b

   MSHAPE,0,2D
   MSHKEY,1
   AMESH,ALL

   !* transducer

   NSEL,S,LOC,Z,dif

   NSLE,U,MID !* do not apply a force at middle nodes

   CM,tr1,NODE
   ALLSEL,ALL

EMTGEN,'tr1','EMTELM1','EMTPNO1','UZ',h1,0,1E-02,0.8854E-05

   !* applying loads and BC

   NSEL,S,LOC,Z,dif+h1
   NSEL,A,LOC,Z,dif+h2
   D,ALL,,0,,,,UZ
   D,ALL,VOLT,0

   CMSEL,S,tr1
   D,ALL,VOLT,v
 
   NSEL,S,LOC,X,0
   NSEL,A,LOC,X,Lm
   NSEL,A,LOC,Y,0
   NSEL,A,LOC,Y,Wm

   D,ALL,UX,0
   D,ALL,UY,0
   D,ALL,UZ,0
   D,ALL,ROTX,0
   D,ALL,ROTY,0
   D,ALL,ROTZ,0

   ALLSEL,ALL

FINISH

/SOLU
   ANTYPE,STATIC

 SOLVE
FINISH

----------------------------------------------------------
transducers in two step
----------------------------------------------------------

.......the same as above........

h1=-0.3   !the same distance
h2=-0.3
a2=75/Lm    !half membrane's length, border beetwen levels

   !* transducer

   NSEL,S,LOC,Z,dif
   NSLE,U,MID !* do not apply a force at middle nodes
   CM,tr,NODE   !* all nodes   

   !*2nd level

   NSEL,S,LOC,Z,dif
   NSEL,R,LOC,X,a2*Lm,(1-a2)*Lm
   NSEL,R,LOC,Y,a2*Lm,(1-a2)*Lm

   NSLE,U,MID !* Ne pas appliquer de force sur les noeuds médians

   CM,tr2,NODE
   ALLSEL,ALL

   !1ere

   NSEL,S,LOC,Z,dif

   NSLE,U,MID !* Ne pas appliquer de force sur les noeuds médians

   CMSEL,U,tr2       ! remove nodes which corresponds to 2nd level

   CM,tr1,NODE
   ALLSEL,ALL

   EMTGEN,'tr2','EMTELM2','EMTPNO2','UZ',h2,0,1E-02,0.8854E-05
EMTGEN,'tr1','EMTELM1','EMTPNO1','UZ',h1,0,1E-02,0.8854E-05

   NSEL,S,LOC,Z,dif+h1
   NSEL,A,LOC,Z,dif+h2
   D,ALL,,0,,,,UZ
   D,ALL,VOLT,0

...........the same as above............

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources