Gravity UDF

kdkcfd · July 1, 2016, 11:45

I want to define time dependent gravity acceleration in X direction in FLUENT.

For example;

t=0 s g=0 m/s^2
t=0.1s g=5 m/s^2
t=0.2s g=9 m/s^2
t=0.4s g=13 m/s^2
t=0.5s g=7 m/s^2
t=0.6s g=-2 m/s^2
...

`e` · July 5, 2016, 17:50

You could modify the gravity term via the text user interface with a Scheme script (run with a calculation activity at the end of each time step). Otherwise, add your own source term to the momentum equation with the DEFINE_SOURCE macro; use conditional statements for your time periods with CURRENT_TIME to return the current simulation time.

July 1, 2016, 11:45	Gravity UDF	#1
kdkcfd New Member Join Date: Oct 2015 Posts: 2 Rep Power: 0	I want to define time dependent gravity acceleration in X direction in FLUENT. For example; t=0 s g=0 m/s^2 t=0.1s g=5 m/s^2 t=0.2s g=9 m/s^2 t=0.4s g=13 m/s^2 t=0.5s g=7 m/s^2 t=0.6s g=-2 m/s^2 ...

July 5, 2016, 17:50		#2
`e` Senior Member Join Date: Mar 2015 Posts: 892 Rep Power: 18	You could modify the gravity term via the text user interface with a Scheme script (run with a calculation activity at the end of each time step). Otherwise, add your own source term to the momentum equation with the DEFINE_SOURCE macro; use conditional statements for your time periods with CURRENT_TIME to return the current simulation time. ghost82 likes this.

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