[TRNSYS-users] Type 56 Thermo Active Layer Resistances

[Devin Rohan <drohan@purdue.edu>]

In the Type 56 manual, it models the thermal network from the supply water to the pipe plane node as resistances placed in series.  For example, if I wanted to find the rate of heat transfer from one node to the next, by using...

Q=[ A*(T1-T2) ] / R

What area would I use, since all the resistance values are in units of [m^2-K/W].  Here's what I was thinking...

Rz: thermal resistance in z-direction along the pipe length--> A=area of the floor surface, since I see the mean temperature as being similar to node k (pipe plane temperature ) and the heat transfer goes up through the floor into the space.

Rw: thermal resistance by forced convection (from fluid to pipe shell) for cylindrical areas--> A=2*pi*Ri*L, the inside surface area of the pipe

Rr: thermal resistance by conduction through the pipe shell--> A=[pi*Ro^2] - [pi*Ri^2], where Ro and Ri are the outside and inside pipe radii

Rx: thermal resistance from outer pipe shell to pipe plane by conduction--> A= floor thickness (since the heat transfer is horizontal)

Please let me know if this is incorrect.  Thank you

-- 
Devin M. Rohan
drohan@purdue.edu