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Sin Input of force via array commands

Sin Input of force via array commands

Sin Input of force via array commands

(OP)
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

RE: Sin Input of force via array commands

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

RE: Sin Input of force via array commands

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

-Brian

RE: Sin Input of force via array commands

(OP)
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

RE: Sin Input of force via array commands

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

RE: Sin Input of force via array commands

(OP)
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

RE: Sin Input of force via array commands

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

RE: Sin Input of force via array commands

(OP)
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.

RE: Sin Input of force via array commands

*vplot,,xdata

that will plot the values of that table parameter

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