Using UDF to define parameter

Oleg V. · January 24, 2017, 03:00

Dear friends!
I am trying to solve transient problem. For my case I need to specify time-depended gravity, but I don't know how to do it. The only thing that I can specify for gravity is parameter. That's why my question is: how can I define the value of the parameter in UDF?
I mean that the value for gravity will be changed in each time step (using real t = CURRENT_TIME).

Oleg

kirmaks · January 24, 2017, 03:23

Hallo, You can replace Your gravity with the source in NS equations and then use source UDF to change the gravity vector with time as it is described here:

UDF to modify gravity via M_gravity[ND_ND] or DEFINE_ADJUST

Best regards, Maksim

Oleg V. · January 24, 2017, 03:55

kirmaks,
Thank you so much!
That's exactly what I need! It helped me to define all gravity components!

January 24, 2017, 03:00	Using UDF to define parameter	#1
Oleg V. New Member Oleg Vlasov Join Date: Oct 2014 Posts: 15 Rep Power: 12	Dear friends! I am trying to solve transient problem. For my case I need to specify time-depended gravity, but I don't know how to do it. The only thing that I can specify for gravity is parameter. That's why my question is: how can I define the value of the parameter in UDF? I mean that the value for gravity will be changed in each time step (using real t = CURRENT_TIME). Oleg

January 24, 2017, 03:23		#2
kirmaks Member KirMaks Join Date: Aug 2016 Posts: 34 Rep Power: 10	Hallo, You can replace Your gravity with the source in NS equations and then use source UDF to change the gravity vector with time as it is described here: UDF to modify gravity via M_gravity[ND_ND] or DEFINE_ADJUST Best regards, Maksim pakk and Oleg V. like this.

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January 24, 2017, 03:55		#3
Oleg V. New Member Oleg Vlasov Join Date: Oct 2014 Posts: 15 Rep Power: 12	kirmaks, Thank you so much! That's exactly what I need! It helped me to define all gravity components!