TLDR: I want to model an earth tube that precools air before it reaches the DOAS in HB 1.2.0
I noticed that HB Legacy had an earth tube component which presumably was referencing this Zone Earthtube component in EP. From what I understand, this object works in a similar fashion to a natural ventilation object with mins and max’s between heating and cooling setpoints.
This is all well and good, however, it is not what I need, nor is it available in HB 1.2.0 (I think!)
Rather, I would like to model an earth tube at the beginning of the DOAS system, effectively precooling outside air before it hits the cooling coil. The simplest way I can think of doing this would be to approximate the air temp that is entering the DOAS (haven’t found a reference yet, but I’m sure it’s out there.) Do any of your know of a method to adjust the DOAS outdoor air supply temp manually in HB 1.2.0(3)? As with many of my HVAC related posts, I suspect the answer might lie with Ironbug…
This is definitely the type of thing that would require either Ironbug or some custom HVAC creation in the OpenStudio App or OpenStudio Measure.
@MingboPeng might have some ideas for how to do something like this in Ironbug. You might also want to ask a question like this on the Unmethours forum since some of the experts there might have some recommendations of which E+ objects to use.
Thank you very kindly, Chris! Apologies for the late reply. I am going to dine into this in the next couple of months so I will report back on my progress!
I am currently working on an EarthTube simulation and wanted to ask how people typically determine the required number of pipes or ducts to satisfy a zone’s cooling/heating load. From my research and testing, a single default pipe is often not sufficient to handle the total airflow or thermal demand of a space. Therefore, determining the required number of pipes seems to be an important part of the design.
I was recently advised to use the ZoneHVAC:EnergyRecoveryVentilator (ERV) component for this setup. The suggested approach was to use the zone-specific ERV component, set the heat exchanger effectiveness to zero, determine the required airflow for the zone, and use the same output variables from the EarthTube/pipe simulation as input variables for the ERV. A single table containing the relevant data should be sufficient.
I was wondering whether this approach is available in the Grasshopper Honeybee-to-OpenStudio workflow. I tried one approach using the Ironbug Energy Recovery Ventilator, but I am not sure whether I am setting it up correctly (Fig attached).
Could anyone please advise whether I am going in the right direction, or suggest another approach that would be more appropriate?
I feel that this should be relatively straightforward, but I may be missing an important step, particularly regarding how to determine the required number of EarthTube pipes.
Thank you in advance for any suggestions or guidance.
