EnergyPlus / Ladybug and Design Flow Rate

ladybug-tools
, ,
1

Hello EnergyPlus and HoneyBee experts!

I am trying to find a way apply Design Flow Rate on a ventilated facade (in my case the outer cladding is a green wall). I understand that the green roof model cannot simply be applied on a vertical facade and that I need to model the cavity, which has a thickness of 10 cm.

For the ventilation I have built volume as a separate zone with a no mass object (OpaqueMatNoMass) between the zone of the appartment / office / … and the green roof / facade.

Now I want to apply the design flow rate on the ventilation (NoMassObject) as described here:

Where can I apply e.g. the BLAST values, windspeed, … in Ladybug / HoneyBee? I tried HB ventilation, but that only has limited possibilites, as I understand.

Thanks in advance!

IMG_2620
IMG_26201920×2560 299 KB

2

Hi,
you can use add_str in ModelToOSM with a panel saying:

ZoneVentilation:DesignFlowRate,
[Object_Name],
[Zone_Name],
[Schedule_Name],
Flow/Zone [or change to another method below],
[Value],
,
,
,
Natural,
,
,
[0.606 for BLAST example],
[0.03636 for BLAST example],
[0.1177 for BLAST example],
[0 for BLAST example],
;

or copy and paste the example in the input/output reference guide for these specific object and change with your parameters.
Best regards
Massimiliano

3

To learn more about how to realise external green walls with EnergyPlus I suggest reading this paper:

Greetings
Massimiliano

1 Like
4

Thank you very much! I really appreciate your input! Great!
I actually had no idea where to put the information in Honeybee …

In addition, this was very helpful:

I think I made a mistake in naming the zones or something. Since I plugged in the panel, I got two errors which can be seen here:

DesignFlowRate
DesignFlowRate3144×1276 333 KB

Does anybody maybe have a clue, what I am missing?

Thanks in advance!

5

I assume the “severe” error causes the “fatal” one.
The “SIMPLE_ACH” schedule is missing in the definitions. I would try to add it inside the additional strings you are providing.
Also assume the name of the thermal zone “Zone_vent” exists in the model, right?

-A.

2 Likes
6

Hey,

thanks for your answer!
I had some issues with the schedules, but now everything seems fine.

Big thanks to everybody!