Hi @SaeranVasanthakumar,
I had a look at this more in depth and I found an easier way to work out the fan power. The method uses Specific Fan Power values (W/(m3/s)) and multiplies these for the airflow rate. The SFP of the system can be defined using the default values in the EN 16798-3 standard (see tables below).
Regarding the airflow in input, I believe with Ideal Air Loads the most appropriate input would be the Outdoor Inlet Flow rate, for a theoretical balanced system that only handles outdoor air supply and zone extract.
So shouldn’t be as I previously thought:
Internal Supply fan + Outdoor Supply fan*2
otherwise this would give the power of three systems running in parallel for AC supply, Outdoor Air and Extract.
GH definition attached
Fan for Ideal Air Load system_v2.gh (652.8 KB)