time derivative of velocity

rystokes · January 5, 2010, 04:25

HI,

Is there any way to define time derivative of velocity term in cfx please?　I 'm quite interested in this term ,and I want to plot the time history of it.

Thanks a lot.

Harry

cfdgremlin · January 5, 2010, 08:36

You should be able to use the '.Time Derivative' operator for most variables in CEL for a transient calculation. For example, for the X component of velocity:

Velocity u.Time Derivative

If this doesn't work, then it will almost certainly work with a User Fortran call to USER_GETVAR.

C

kingjewel1 · January 11, 2010, 18:17

I looked for the Time Derivative function but couldn't see it either in Pre or Post. Could you specify where to find it please?

January 5, 2010, 04:25	time derivative of velocity	#1
rystokes New Member harry Join Date: May 2009 Posts: 29 Rep Power: 17	HI, Is there any way to define time derivative of velocity term in cfx please?　I 'm quite interested in this term ,and I want to plot the time history of it. Thanks a lot. Harry

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January 5, 2010, 08:36		#2
cfdgremlin Member Join Date: Dec 2009 Posts: 44 Rep Power: 17	You should be able to use the '.Time Derivative' operator for most variables in CEL for a transient calculation. For example, for the X component of velocity: Velocity u.Time Derivative If this doesn't work, then it will almost certainly work with a User Fortran call to USER_GETVAR. C

January 11, 2010, 18:17		#3
kingjewel1 Senior Member Join Date: Jul 2009 Posts: 260 Rep Power: 18	I looked for the Time Derivative function but couldn't see it either in Pre or Post. Could you specify where to find it please?