Contents - Index


SR_2

 

 

Function SR_2(a, k) returns the thermal resistance between the surface of a circular contact area that is exposed to a uniform heat flux and is located on the surface of a semi-infinite half-space.  The resistance is based on the area averaged temperature of the circle (SR_3 provides the resistance based on the center temperature).

 

The calling protocol is:

 

R = SR_2(a, k)

 

Inputs:

a = radius of the circular contact [m or ft]

k = thermal conductivity of the material [W/m-K or Btu/hr-ft-R]

 

Outputs:

R = resistance [K/W or R-hr/Btu]

 

Rohsenow, W.M, J. P. Hartnett, and Y. I. Cho, Handbook of Heat Transfer, 3rd Edition, McGraw Hill, (1998).

 

Example: 

$UnitSystem SI Mass J K Pa

$VarInfo R2 units=K/W

a=0.01 [m]

k=100 [W/m-K]

R2=sr_2(a,k)

 

{Solution:

R2=0.2702 [K/W]}

 

Spreading Resistance Index