[lauda]

Hello there,

I'm trying to model a heat exchanger (HX) as porous model. The HX consists of a box with a large number of pipes mainly parallel to each other.. I was thinking to use the isotropic loss option of the porous domain. I have then calculated the liner and quadratic resistance coefficients (CR1 and CR2 in CFX-theory tutorial). I would appreciate if you could confirm that the equations I have used (see below) are correct.

CR1 = K_loss * rho / 2 = Dp / (L*v**2)

where rho is the density, Dp is pressure drop across the HX, L is the HX lenght and v is the stream flow velocity at the HX inlet.


CR2= mu / K_perm = dP / (L * V_s)

where V_s= volume flow rate/cross sectional area.

thanks for your help