Split Airflow to terminal

[HJMec]

Hi everyone,

I am in the process of creating and sizing duct work for a specific project in Revit. Due to space constraints my boss has asked me to split a single supply (100 l/sec) duct into 2 separate flex ducts (50 l/sec), the catch being that they both connect to a single diffuser!! Revit is obviously not happy and cannot calculate flow for this section of duct. (He did mention that this is not a common occurrence but that he has done this previously (he has over 30 years experience so I trust he has :))

Has anyone come across this and is there a way to get Revit to recognize what is happening?

Look forward to some feedback and thanks in advance.

Regards

Henry

[jtgel]

Connect a rd tee or Y to the diffuser & the main duct & then connect your flexes.

[robert.klempau · Accepted solution]

Hello @HJMec,

Is it correct that you need something like this in your project?

 

If so, you are right. Revit can't handle parallel duct system without a special fitting or accessory in the parallel duct runs.

the way I solved is to exchange the normal Tee with a special Tee.

See attachment. (2019)

The Tee has, at the main connector a Calculated Flow configuration and a flow direction In.

Both other connectors have a Preset Flow configuration and a flow direction Out.

The flow in the connectors are linked to a Flow parameter.

The Flow of the two Preset connectors is 0.5 x the main flow.

[HJMec]

Thanks for your quick response guys, works perfectly for splitting the flow...have some flow mismatch issues in the system but should be able to get to the bottom of it. Appreciate the help.