Transient Thermal Module

Martin_Sz · July 14, 2021, 11:31

Hello
Anyone know how to setup different temperatures on different bodies??
If i define reference temperatures on geometry elements for example 1 body 120 C , 3 next bodies 25 C , and initial temperature on 25C . After simulation is done, all elements have 25C (in all solution time) . Maybe I do something wroga, maybe i need define some additional options ???

Martin_Sz · July 17, 2021, 07:48

Anyone hace idea what I do wrong ???

evcelica · July 23, 2021, 14:11

Use multiple load steps. 1 for setting the initial conditions, and the next for your transient calculations.
First loadstep, set the initial temperatures as Boundary conditions.
Turn off time integration for that timestep. It is in analysis settings. Then it will solve as steady state for that step.
In the next load step, deactivate those temperature boundary conditions. Time integration should be on for the rest of the timesteps when you want to solve the transient behavior.

July 14, 2021, 11:31	Transient Thermal Module	#1
Martin_Sz Senior Member Marcin Join Date: May 2014 Location: Poland, Swiebodzin Posts: 232 Rep Power: 12	Hello Anyone know how to setup different temperatures on different bodies?? If i define reference temperatures on geometry elements for example 1 body 120 C , 3 next bodies 25 C , and initial temperature on 25C . After simulation is done, all elements have 25C (in all solution time) . Maybe I do something wroga, maybe i need define some additional options ??? __________________ Quick Tips and Tricks, Tutorials FLuent/ CFX (CFD) https://howtooansys.blogspot.com/

July 17, 2021, 07:48		#2
Martin_Sz Senior Member Marcin Join Date: May 2014 Location: Poland, Swiebodzin Posts: 232 Rep Power: 12	Anyone hace idea what I do wrong ??? __________________ Quick Tips and Tricks, Tutorials FLuent/ CFX (CFD) https://howtooansys.blogspot.com/

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July 23, 2021, 14:11		#3
evcelica Senior Member Erik Join Date: Feb 2011 Location: Earth (Land portion) Posts: 1,167 Rep Power: 23	Use multiple load steps. 1 for setting the initial conditions, and the next for your transient calculations. First loadstep, set the initial temperatures as Boundary conditions. Turn off time integration for that timestep. It is in analysis settings. Then it will solve as steady state for that step. In the next load step, deactivate those temperature boundary conditions. Time integration should be on for the rest of the timesteps when you want to solve the transient behavior.