Modal Analysis

performed with ANSYS

Modal Analysis of a Resonant diaphragm pressure sensor based on a silcon MEMS microstructure.

 PERFORM A MODAL ANALYSIS
  THIS WILL BE A NEW ANALYSIS


 USE HOUSEHOLDER METHOD
  EXTRACT    5 MODES
  PRINT      0 REDUCED MODES
  NORMALIZE THE MODE SHAPES TO THE MASS MATRIX


 NUMBER OF MODES TO EXPAND=     5
  DO NOT CALCULATE ELEMENT RESULTS

 PARAMETER TOTL     =     50.00000    

 TOTAL MASTER D.O.F.=    50
 NO ROTATIONAL MASTER KEY=  1

*****  ANSYS SOLVE    COMMAND  *****

***** ANSYS - ENGINEERING ANALYSIS SYSTEM  REVISION 5.0A    *****
 HAHN-SCHICKARD    VERSION=HP 9000/7XX   11:35:43  AUG 24, 1994 CP=      1.000
 FOR SUPPORT CALL THOMAS FABULA    PHONE 07721/943-239    FAX                 

  Resonant diaphragm pressure sensor                                           

                    
S O L U T I O N   O P T I O N S

   PROBLEM DIMENSIONALITY. . . . . . . . . . . . .3-D         
   DEGREES OF FREEDOM. . . . . . UX   UY   UZ   ROTX ROTY ROTZ 
   ANALYSIS TYPE . . . . . . . . . . . . . . . . .MODAL                
   EXTRACTION METHOD. . . . . . . . . . . . . .REDUCED     
   NUMBER OF MODES TO EXTRACT. . . . . . . . . . .     5
   NUMBER OF REDUCED MODES TO PRINT. . . . . . . .     0
   NUMBER OF MASTER DOF. . . . . . . . . . . . . .    50
   NUMBER OF MODES TO EXPAND . . . . . . . . . . .     5
   ELEMENT RESULTS CALCULATION . . . . . . . . . .OFF

                      
L O A D   S T E P   O P T I O N S

   LOAD STEP NUMBER. . . . . . . . . . . . . . . .     1
   PRINT OUTPUT CONTROLS . . . . . . . . . . . . .NO PRINTOUT
   DATABASE OUTPUT CONTROLS. . . . . . . . . . . .ALL DATA WRITTEN
 

***** CENTROID, MASS, AND MASS MOMENTS OF INERTIA *****

  CALCULATIONS ASSUME ELEMENT MASS AT ELEMENT CENTROID


  TOTAL MASS =   .49282E-08

                           MOM. OF INERTIA         MOM. OF INERTIA
     CENTROID               ABOUT ORIGIN           ABOUT CENTROID

  XC =   4.6000          IXX =    .1387E-06      IXX =    .3441E-07
  YC =   4.6000          IYY =    .1387E-06      IYY =    .3441E-07
  ZC =   .00000E+00      IZZ =    .2774E-06      IZZ =    .6882E-07
                         IXY =   -.1043E-06      IXY =    .1323E-22
                         IYZ =    .0000E+00      IYZ =    .0000E+00
                         IZX =    .0000E+00      IZX =    .0000E+00


*** MASS SUMMARY BY ELEMENT TYPE ***

  TYPE      MASS
     1   .492816E-08

 Range of element maximum matrix coefficients in global coordinates
 Maximum= 1909.14616 at element 20.                                      
 Minimum= 1909.14616 at element 55.                                      

*** ELEMENT MATRIX FORMULATION TIMES
  TYPE  NUMBER   ENAME      TOTAL CP  AVE CP

     1     100  SHELL43       1.640     .016
 Time at end of element matrix formulation CP= 2.87.                     
 
 Estimated number of active DOF= 486.                                    
 Maximum wavefront= 124.                                                 
 
 Time at end of matrix triangularization CP= 4.05.                       
 Equation solver maximum pivot= 7635.86132 at node 20 UX.                
 Equation solver minimum pivot= 1.29617023 at node 109 ROTZ.             



***** EIGENVALUE (NATURAL FREQUENCY) SOLUTION *****

  MODE    FREQUENCY (CYCLES/TIME)

    1      4202.44957    
    2      8728.82514    
    3      8885.92158    
    4      12931.8617    
    5      16428.5348    


*** PROBLEM STATISTICS
  ACTUAL NO. OF ACTIVE DEGREES OF FREEDOM =    436
  R.M.S. WAVEFRONT SIZE =   109.6
  NUMBER OF MASTER DEGREES OF FREEDOM =    50


*** ANSYS BINARY FILE STATISTICS
  BUFFER SIZE USED=  4096
         .531 MB WRITTEN ON ELEMENT MATRIX FILE: file.emat
         .266 MB WRITTEN ON ELEMENT SAVED DATA FILE: file.esav
         .391 MB WRITTEN ON TRIANGULARIZED MATRIX FILE: file.tri
         .047 MB WRITTEN ON MODAL MATRIX FILE: file.mode
         .125 MB WRITTEN ON RESULTS FILE: file.rst


Calculations performed at HSG-IMIT : www.hahn-schickard.de