Dry cooler modelling

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For DesignBuilder free-cooling heat exchanger go to HVAC system and select waterside economizer template.

Replace the cooling tower with a dry cooler.

Right click on CHW Loop Supply Side and chose the HX working schedule. Don’t forget to enter the HX design flow rate and free cooling and control type. Adapt your system as needed.

Hi, I would have a further question about the FluidCooler model in EnergyPlus. I am trying to figure out the sizing approach, but there is something I cannot understand.

At page 287 of the Engineering Reference document, it says that the design air flow can be calculated by the formula highlighted in red in the attach screenshot. Does anybody know the rationale behind this formula?

C:\fakepath\FluidCooler.png

On the OpenStudio front:

Phase change material is modeled using MaterialProperty:PhaseChange in EnergyPlus. This object is not available directly in OpenStudio, but could be added to a model via an EnergyPlus Measure.

A dry cooler is called a FluidCooler in EnergyPlus. It is available in OpenStudio. You would attach this to the supply side of a PlantLoop.

Since DesignBuilder uses EnergyPlus as the engine, it may well already expose these objects. It should be easier to check now that you know their EnergyPlus names.

There are dry coolers in EnergyPlus. The two objects for this are FluidCooler:SingleSpeed and FluidCooler:TwoSpeed.

I don't know if they are accessible in DesignBuilder for sure or not as I've not used it, but I've just found one email in my inbox that says they added Fluid Coolders to DB last June.

As far as OpenStudio: FluidCoolers just got included in the 1.9.0 release candidate. Ice Thermal Storage was already in 1.8.0.

I think the only thing you'll miss is the Material:PhaseChange object but you can access it through an E+ measure I guess.