Sin Input of force via array commands

[netown]

Hi could anyone tell me where can I find very clear instructions of sine input of force via array commands? or is there an alternative to this?

Thanks alot for reading this

Regards,
Dunstan

 

[doatis]

You can use the function editor. Search the ANSYS help for tabular loads, then look for section "2.5.15. Applying Loads Using Function Boundary Conditions"

If your goal is to apply a sinusoidal force distribution to simulate a bearing load (i.e. trying to shear a pin out of a lug), look at using SURF154s. Very easy to do in Workbench by using the 'Bearing Load' condition.

Hope this helps,
Doug

 

[Stringmaker]

Dunstan,
Are you applying a sinusoidal load in a spectrum or harmonic analysis? If so loads are automatically assumed to vary sinusoidally.

-Brian

 

[netown]

Hi Doug n Brian,

Firstly, thanks for the replies. I am trying to apply a sinusoidal force to simulate a vibration at the end of a beam. I was told it was suppose to be a transient analysis as the response is not to be harmonic. Thus, I strong believe is a mode-superposition transient analysis. (Please correct me if I am wrong.)

So would the function editor still apply? Sorry if I was unclear earlier on.

So am I right that I am kinda of fix to array parameters input style?

Best Regards,
Dunstan

 

[doatis]

Dunstan,

Sorry, I misread your original question. If you are doing a sinusoidally varying load vs. time to simulate vibration, you don't want to use the function editor. I was under the impression that the load varied sinusoidally over distance.

You want to do a harmonic analysis. Look up the help in section 4.4 "Performing a Harmonic Analysis" and it shows that when you apply a load, you specify not only the magnitude, but the phase angle as well.

Hope this helps,
Doug

 

[netown]

Hi

I was wondering if this will work for the input of force in a half sine wave..Can anyone help me check for errors?


*DEL,_FNCNAME
*DEL,_FNCMTID
*DEL,_FNC_C1
*DEL,_FNC_C2
*DEL,_FNCCSYS
*SET,_FNCNAME,'example'
*DIM,_FNC_C1,,1
*DIM,_FNC_C2,,1
*SET,_FNC_C1(1),100
*SET,_FNC_C2(1),50
*SET,_FNCCSYS,0
! /INPUT,xansys.func,,,1
*DIM,%_FNCNAME%,TABLE,6,5,1,,,,%_FNCCSYS%
!
! Begin of equation: {X}+A*sin(omega*{TIME})
*SET,%_FNCNAME%(0,0,1), 0.0, -999
*SET,%_FNCNAME%(2,0,1), 0.0
*SET,%_FNCNAME%(3,0,1), %_FNC_C1(1)%
*SET,%_FNCNAME%(4,0,1), %_FNC_C2(1)%
*SET,%_FNCNAME%(5,0,1), 0.0
*SET,%_FNCNAME%(6,0,1), 0.0
*SET,%_FNCNAME%(0,1,1), 1.0, -1, 0, 1, 18, 3, 1
*SET,%_FNCNAME%(0,2,1), 0.0, -1, 9, 1, -1, 0, 0
*SET,%_FNCNAME%(0,3,1), 0, -2, 0, 1, 17, 3, -1
*SET,%_FNCNAME%(0,4,1), 0.0, -1, 0, 1, 2, 1, -2
*SET,%_FNCNAME%(0,5,1), 0.0, 99, 0, 1, -1, 0, 0
! End of equation: {X}+A*sin(omega*{TIME})
!-->

Regards,
Dunstan

 

[DanJordy]

what about doing something like this, for a half sine:

A = - 9.8e6 ! amplitude
xtime=.0001 ! seconds
ttime=.0001*3

asize=75 ! data resolution
pi=3.141592654

*dim,xdata,table,asize,1,1,time
xdata(1)=0.0
xdata(1,0)=0.0

*afun,rad

*do,i,2,asize
xfr=pi*(i/asize)
xdata(i,0)=i/asize*xtime ! time
xdata(i)=(A*sin(xfr)) ! data
*enddo

 

[netown]

Hi DanJordy,

Can you tell me how will I be able to plot out the inital input of the forces? In order to verify that the input is a half-sine curve? ( GUI or Batch commands? )

Thankx for your time..I be trying that string you supplied and will feedback soon.

 

[DanJordy]

*vplot,,xdata

that will plot the values of that table parameter