How to write UDF for Dynamic Viscosity

ramakant · August 16, 2018, 22:05

Dear All

I need your comments and suggestions for the given equation. Please find the attached file herewith.

Thank you

Ramakant

amod_kumar · August 18, 2018, 11:33

You can find an example in UDF manual, following should work.

DEFINE_PROPERTY(visc_T, c, Tp) {
real mu; real a = C_T(c,t);
mu = 2.414e-05 * pow(10, 247.8/(Tp - 140));
return mu;
}

The linkhttp://cfdyna.com/CFDHT/scriptsMacros.html#UDF might help you understand how UDFs are written.

ramakant · August 19, 2018, 00:04

Thank you very much...

dsub5 · May 10, 2019, 06:44

hello everyone. i have to create udf for dynamic viscosity and thermal conductivity coefficient. but have no idea about codes.

here is the formulas. if anyone can help me, i wii be glad.

mu=(3.4*10^-7*T^2)-(2.3*10^-4*T)+(3.9*10^-2)

k=0.004961*T-0.8078

August 18, 2018, 11:33	How to write UDF for Dynamic Viscosity	#2
amod_kumar Member Amod Kumar Join Date: Jan 2010 Location: Delhi, India Posts: 39 Rep Power: 16	You can find an example in UDF manual, following should work. DEFINE_PROPERTY(visc_T, c, Tp) { real mu; real a = C_T(c,t); mu = 2.414e-05 * pow(10, 247.8/(Tp - 140)); return mu; } The linkhttp://cfdyna.com/CFDHT/scriptsMacros.html#UDF might help you understand how UDFs are written. ramakant likes this.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
[Helyx OS] Helyx-OS (GUI for SnappyHexMesh	elvis	OpenFOAM Community Contributions	210	January 30, 2017 18:57
Help - UDF for solid shear viscosity	nbh2801	FLUENT	0	April 21, 2006 07:49
Trying to Write pitch and Plunge UDF	Alex	FLUENT	0	March 18, 2006 16:14
How to write UDF for pitching&plunging airfoil?	Alex	FLUENT	0	March 17, 2006 12:37
Turbulent Viscosity UDF	Raphael	FLUENT	2	January 23, 2006 04:04

August 19, 2018, 00:04		#3
ramakant Senior Member Ramakant Gadhewal Join Date: Apr 2010 Location: Chemical Engineering,National Institute of Technology,Warangal (T.S.),India Posts: 130 Rep Power: 16	Thank you very much...

May 10, 2019, 06:44		#4
dsub5 New Member dogan sublimis Join Date: May 2019 Posts: 3 Rep Power: 7	hello everyone. i have to create udf for dynamic viscosity and thermal conductivity coefficient. but have no idea about codes. here is the formulas. if anyone can help me, i wii be glad. mu=(3.410^-7T^2)-(2.310^-4T)+(3.910^-2) k=0.004961T-0.8078