# Thermal conductivity issue

 Register Blogs Members List Search Today's Posts Mark Forums Read

 March 19, 2014, 09:21 Thermal conductivity issue #1 New Member   Jarda Chlup Join Date: Aug 2013 Posts: 21 Rep Power: 12 Hello, I have trouble with thermal conductivity setting. I have a lot of solid domains, where I have to set thermal conductivity on cylindrical components, but these domains are in circular patern and axis, which I need for thermal conductivity setting, are rotating on cyrcle.Does anybody know if it is possible to set equation of circle like rotation axis for cylindrical coord? Normal setting for cylindrical components is: THERMAL CONDUCTIVITY: Option = Orthotropic Cylindrical Components Thermal Conductivity Axial Component = 5 [W m^-1 K^-1] Thermal Conductivity Theta Component = 10 [W m^-1 K^-1] Thermal Conductivity r Component = 15 [W m^-1 K^-1] AXIS DEFINITION: Option = Two Points Rotation Axis From = 0 [m],0 [m],0 [m] Rotation Axis To = 0 [m],0 [m],1 [m] END END My situation THERMAL CONDUCTIVITY: Option = Orthotropic Cylindrical Components Thermal Conductivity Axial Component = 5 [W m^-1 K^-1] Thermal Conductivity Theta Component = 10 [W m^-1 K^-1] Thermal Conductivity r Component = 15 [W m^-1 K^-1] AXIS DEFINITION: Option = Two Points Rotation Axis From = (sqrt(y^2-R^2)) [m],(sqrt(x^2-R^2)) [m],0 [m] Rotation Axis To = (sqrt(y^2-R^2)) [m],(sqrt(x^2-R^2)) [m],1 [m] END END Where R is radius of circle. But it's probably wrong syntax. Does anybody have idea how is it possible to solve this issue? Thanks a lot

 March 20, 2014, 02:03 #2 Senior Member   Bharath kumar Join Date: Apr 2009 Posts: 169 Rep Power: 17 I think there is no problem in syntax.You are getting any error.

 March 20, 2014, 05:11 #3 Super Moderator   Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,750 Rep Power: 143 You have misintepreted the axis from/to fields. These fields define two points through which CFX places a line and that defines the axis. So this should have a constant x,y,z point, not a CEL expression.

 March 20, 2014, 10:38 #4 Senior Member   Edmund Singer P.E. Join Date: Aug 2010 Location: Minneapolis, MN Posts: 511 Rep Power: 20 Glenn is right. You have described an infinately varing material condition. You need to define a separate material property for each solid with each axis defined through the set centerline of each solid.