How to define boundary conditions for an oscillating heat pipe

yufeiai · April 21, 2016, 17:19

Hi guys,

I am simulating an oscillating heat pipe, which is a capillary tube arranged in a serpentine manner and forms a close loop. It doesn't have flow inlet and outlet. It is partially filled with water. Water evaporates and the vapor rises under the force of a heater at the bottom of the pipe. Vapor then condensed at the top of the heat pipe. Therefore it forms a two-phase flow in the pipe.

I'm wondering how I should deal with boundary conditions. There is motion with the fluid flow, but actually no inlet or outlet in reality. I'm not sure if I should define a velocity inlet or pressure outlet somewhere？

Also can I define a heat flux at the walls at bottom without UDF functions?

Thanks for any comment or suggestion!

yufeiai · April 21, 2016, 17:21

I did the simulation in ANSYS FLUENT.

judex · December 4, 2017, 09:56

Quote:

Originally Posted by yufeiai

I did the simulation in ANSYS FLUENT.

can you share this? I get stuck in this case, too boring, I try my best to do this ,

April 21, 2016, 17:19	How to define boundary conditions for an oscillating heat pipe	#1
yufeiai New Member Yufei Ai Join Date: Apr 2016 Location: Houston TX Posts: 3 Rep Power: 10	Hi guys, I am simulating an oscillating heat pipe, which is a capillary tube arranged in a serpentine manner and forms a close loop. It doesn't have flow inlet and outlet. It is partially filled with water. Water evaporates and the vapor rises under the force of a heater at the bottom of the pipe. Vapor then condensed at the top of the heat pipe. Therefore it forms a two-phase flow in the pipe. I'm wondering how I should deal with boundary conditions. There is motion with the fluid flow, but actually no inlet or outlet in reality. I'm not sure if I should define a velocity inlet or pressure outlet somewhere？ Also can I define a heat flux at the walls at bottom without UDF functions? Thanks for any comment or suggestion!

April 21, 2016, 17:21		#2
yufeiai New Member Yufei Ai Join Date: Apr 2016 Location: Houston TX Posts: 3 Rep Power: 10	I did the simulation in ANSYS FLUENT. dolati likes this.

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