[TRNSYS-users] TRNFlow_ Fan_ Diverging and Converging tees

[ali shahrouzian]

Dear all TRNSYS users,

I am modeling a forced air furnace system to satisfy heating demands of a
residential building. To simulate the building's thermal load and consider
the effects of air transfer between thermal zones, I've used Type
56-TRNFlow. As you know, when TRNFLOW is turned on, in the simulation the
defined infiltrations, ventilations and couplings will be replaced with the
defined TRNFLOW data. Thus, in TRNFlow, I must define a fan, a heating
coil, and a ducting system in order to model the forced air furnace system.

However, I am having some trouble modeling a fan and fittings (Tee).

1- In TRNFlow, how can I control the value of a fan's air flow rate? My
goal is to have the air blown into the building by a supply fan at a
constant and certain rate. It seems that due to changes in pressure
differences between auxiliary nodes, the air flow rate of the fan cannot
remain constant either.

2- How can I input the value of the flow rate of a "straight duct" in
TRNFlow? It seems that I can only input the values of the friction loss and
the dynamic loss.

3- How can I model a diverging tee or a converging tee as an air link in
TRNFlow. For example, as for diverging tee, if I want to send 30% of the
flow rate in the main duct to the first branch and the rest to the second
branch, how can I do this?

I would appreciate it if anyone helps me in these cases.

Best,
Ali
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/trnsys-users-onebuilding.org/attachments/20221124/4805e366/attachment-0001.htm>