[Anjishnu Choudhury]

I am having a difficult time in finding the source files of algorithms involved in evaluating the dynamic contact angles. And when the angles are specified, how does it relate with the alpha-field?

[chrisb2244]

The sources for the alphaContactAngles can be found in

.../OpenFOAM-x.y.z/src/transportProperties/twoPhaseProperties/alphaContactAngle/

where x.y.z is your version number, and ... implies your installation path, probably /home or /home/username, I guess? In those cases, ~/OpenFOAM-2.y.z/rest/of/path should probably work.

You can use find . -iname *contactAngle* within the OpenFOAM source tree (.../src) to find these files, but probably it would work from any parent directory (I imagine there are not many other files on your system called *contactAngle*)

[Anjishnu Choudhury]

Hey,
I am confused with few terms like, Uwall(Up.patchInternalField() - Up). What does it physically mean?

How is the Uwall (or Up) evaluated (or taken input from user) ?

Thanks in advance!

[rasool_soofi]

Originally Posted by Mahdi2010

Hi all
I am still trying to understand how ''dynamiccontactangle'' works in OpenFOAM.
Of course thetaA and thetaR are determined based on the material properties of the surface, but ''utheta'' is still the question. What does it mean exactly?

Hi,


uTheta is a scaling factor with same dimensions as velocity (LT^-1). It affects the rate at which the contact angle changes when the capillary number changes. I usually run the model without contact angle definition and see what is the range of velocity near to the wall at the interface and based on that will choose an appropriate scaling factor, uTheta. Maybe the name "uTheta" is misleading because it's a velocity not an angle/angular velocity.



Dynamic Contact Angle Definition (dynamicAlphaContactAngle)


Good luck

[alimea]

Originally Posted by rasool_soofi

Hi,


uTheta is a scaling factor with same dimensions as velocity (LT^-1). It affects the rate at which the contact angle changes when the capillary number changes. I usually run the model without contact angle definition and see what is the range of velocity near to the wall at the interface and based on that will choose an appropriate scaling factor, uTheta. Maybe the name "uTheta" is misleading because it's a velocity not an angle/angular velocity.



Dynamic Contact Angle Definition (dynamicAlphaContactAngle)


Good luck

Hi guys

I have a question about uTheta.

Could you please give me an explanation about it? What is it?

I solved my case one time with uTheta = 2 and another time with uTheta = 0.01, and found that my case is very sensitive to the uTheta value. How can we select the best value for uTheta?

Thanks