Contents - Index


SR_9

 

 

Function SR_9(a, b, k) returns the thermal resistance between the surface of a doubly connected, square 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 average temperature of the contact.  

 

The calling protocol is:

 

R = SR_9(a, b, k)

 

Inputs:

a = half-width of inner square [m or ft]

b = half-width of outer square [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 Radian

$VarInfo R9 units=K/W

a=0.8 [m]

b=1 [m]

k=1 [W/m-K]

R9=sr_9(a,b,k)

 

{Solution:

R9 = 0.2474 [K/W]}

 

 

Spreading Resistance Index