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Calculating and Applying Transient Unbalance Load

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iboby

Mechanical
Dec 6, 2014
12
Hello,
I am modeling a rotating shaft with an unbalance force due to an eccentric disk at the middle by APDL. The rotation is prescribed as: omega(time)=A1*cos(pi*time/T1)/2
My questions are:
1-How should I calculate the unbalance force resulted by this rotation in transient analysis? I tried to use function editor and array parameter but I got ill results. I used the following loop to calculate the unbalance force but it was not successful:
tt=0
*do,iloop,1,25000
velVal = velTab(iloop,1)
vel2 = velVal**2
rotVal = rotTab(iloop,1)
accVal = accTab(iloop,1)
sinr = sin(rotVal)
cosr = cos(rotVal)
fxTab(iloop,1)= F0*(-vel2*sinr + accVal*cosr)
fyTab(iloop,1)= F0*( vel2*cosr + accVal*sinr)
tt = tt + 0.0001
*enddo
I obtained the above data tables by inserting their corresponding functions in the "function editor" and getting the corresponding tables via its dialog box and then used *tread command to filling the data tables.
 
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