Axis B.C in multiphase problem

SH_P · December 22, 2011, 09:58

Hi,
I am going to simulate a drop in a tank (2 phases), using VOF model. my geometery is 2D with a axis, as shown in the figure and I impose the initial position of the drop using UDF, but I'm getting error when I try to solve the problem in Fluent. I think the problem arise from the axis BC. and its portion with different phase.
Does anybody have any idea how to fix it...?
Thanks...

shk12345 · December 22, 2011, 18:46

Try to patch the region with the liquid instead of giving the udf.

SHK

SH_P · December 23, 2011, 01:50

Quote:

Originally Posted by shk12345

Try to patch the region with the liquid instead of giving the udf.

SHK

Thanks for your answer, but could you please explain in more detail what is the meaning of patching a region. I am somewhat new to Fluent...

SH_P · December 23, 2011, 05:16

Quote:

Originally Posted by shk12345

Try to patch the region with the liquid instead of giving the udf.

SHK

I tried patching, but I still get AMG Solver error in Fluent solver.I thinks there is a problem with my mesh and the way I define faces in it. my mesh consists of two faces (drop and surrounding) with axis composed of 3 segments. Do you have any idea how to resolve the problem?
Thanks...

shk12345 · December 23, 2011, 08:28

take axis as a single axis and then try it.Dont divide it into zones.

SH_P · December 23, 2011, 09:03

Quote:

Originally Posted by shk12345

take axis as a single axis and then try it.Dont divide it into zones.

How can I make to different faces without separating axis?

SH_P · December 23, 2011, 11:27

I defined a region in adopt window in Fluent and patched it, also my axis is composed of only one segment. but I still get the AMG Sokver Error.

SH_P · December 23, 2011, 11:32

I think the problem is originated from axis BC itself because I get the same error even without any drop defined in the domain (with only one phase in VOF), whereas I have no problem when I change the axis into wall.

shk12345 · December 24, 2011, 12:54

hi
try to the simulation with complete bubble in the center with walls on both the side.
SHK

December 22, 2011, 09:58	Axis B.C in multiphase problem	#1
SH_P Member Soroush Join Date: Mar 2010 Posts: 52 Rep Power: 16	Hi, I am going to simulate a drop in a tank (2 phases), using VOF model. my geometery is 2D with a axis, as shown in the figure and I impose the initial position of the drop using UDF, but I'm getting error when I try to solve the problem in Fluent. I think the problem arise from the axis BC. and its portion with different phase. Does anybody have any idea how to fix it...? Thanks...

December 22, 2011, 18:46	hi	#2
shk12345 Senior Member shoeb khan Join Date: Nov 2011 Posts: 179 Rep Power: 14	Try to patch the region with the liquid instead of giving the udf. SHK SH_P likes this.

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December 23, 2011, 08:28		#5
shk12345 Senior Member shoeb khan Join Date: Nov 2011 Posts: 179 Rep Power: 14	take axis as a single axis and then try it.Dont divide it into zones.

December 23, 2011, 11:27		#7
SH_P Member Soroush Join Date: Mar 2010 Posts: 52 Rep Power: 16	I defined a region in adopt window in Fluent and patched it, also my axis is composed of only one segment. but I still get the AMG Sokver Error.

December 23, 2011, 11:32		#8
SH_P Member Soroush Join Date: Mar 2010 Posts: 52 Rep Power: 16	I think the problem is originated from axis BC itself because I get the same error even without any drop defined in the domain (with only one phase in VOF), whereas I have no problem when I change the axis into wall.

December 24, 2011, 12:54		#9
shk12345 Senior Member shoeb khan Join Date: Nov 2011 Posts: 179 Rep Power: 14	hi try to the simulation with complete bubble in the center with walls on both the side. SHK