Hi
I have a problem with bonding process modelling to obtain thermal stress resulting in deformation of the structure. The device contains two materials that are bonded in a specific temperature. Then the device is cooled to ambient temperature. Due to difference of thermal expansion...
...However I apply a stres only on shell element, not on trans.
Here is the script:
FINISH
/CLEAR
/FILNAME,mem50shell,0
/CWD,'C:\temp\ANSYS'
!* membrane
Lm=300
Wm=300
Tm=5 !* Epaisseur de la membrane 3e-6 / 1e-6
dif=5
h=-1
V=0
!* membrane_division
b=20
/PREP7
ET,1,SHELL181
R,1,Tm...
...but both solutions result in text file divided into pages.
The other way is to save values from all path points to a variable and export them into file:
*CFOPEN,filename,ext,,APPEND
*do,k,1,path_division
PSEL,itemname,pathname
*get,variable,PATH,0,ITEM,itemname,pathpt,k
*end...
...stress resulting from applied pressure on whole membrane
Is it normal? If one consider the equation of perfectly membrane (Timoshenko theory):
D*h^3*$$w + S*h*$w = P
where: D - rigidity, h - membrane thickness, S - residual stress, $ - Laplace operator, P - pressure
the deflection should...
Ok, now it works.
The first problem was this what jiligeo have noticed. The second thing is that the initial stress is applied to a material. So i had to simulate a membrane with a substrate.
Another question.
Does anybody know what values od stress should i use to simulate a membrane made of a...
...I would like to have a file like this one created in GUI: List -> results -> path data -> file -> save as.. but without following lines:
PRINT ALONG PATH DEFINED BY LPATH COMMAND. DSYS= 0
***** PATH VARIABLE SUMMARY *****
Thanks a lot
Regards
...results summary. The same for a membrane without load.
p.s. i don't want LD
------------------------------
FINISH
/CLEAR
/CWD,'C:\temp\ansys'
!* membrane
Rad=150
Tm=5
!* membrane_division
b=30
!* electrode_distance
h=-1
dif=20
!* voltage
v=5
/PREP7
ET,1,SHELL63
R,1,Tm...
...membrane clamped on edge without damping, large deformation and stress stiffening. Such system can be expressed by following formula:
mw'' + Kw = P*S
where: m - mass, K - spring constant, P - external pressure, S - area
Since external pressure is constant the modes frequencies become...
Hi
I dont know how to perform a modal analysis with loads. I'm trying to find modes frequencies of membrane under pressure but applying a pressure changes nothing, membrane still oscillate around zero deflection. I know that constant load doesn't change frequencies but later i want to apply an...
...The classical law governing membrane's behavior is (developed by Timoshenko, "theory of plates and shells"):
laplacian^2 (w(x,y)) = P / ( D*h^3 )
w(x,y) - membrane's deflection
P - applied pressure
D - rigidity
h - membrane's thickness
In case of electrostaic pressure:
Pe = eps * V^2 /...
...I took all voltage values from 0V to pull-in.
I've also calculated the pull-in voltage using an equation:
Electrostatic pressure = permittivity * voltage^2 / ( 2 * ( gap - deflection)^2 )
In many articles this equation is used and was also compared with ANSYS, the difference was very small...
...like to store Z displacement of node 30
each time in results2.dat only FINISH line is stored (amount correspond to steps value)
---------
steps=2
*dim,result,array,steps - two steps
*dim,volts,array,3 - array with different load values
volts(1)=10
volts(2)=100
volts(3)=1000...
I would like to perform one simulation which has a few steps:
- one load is changing and after each step result from one node i stored in file
How to do this using loops?
thx
Hi
I have to simulate a pressure sensor built on closed membrane. In the cavity there is the air (atmospheric pressure) and the sensor is surrounded by liquid. I would like to perform a transient analysis (i'd like to know the sensor response to ambient pressure changes). How to model the air in...
