Dear all,
I’m trying to simulate the effects of an earthtube ventilation system in an exisisting building. If I remember well in the Legacy version there was a special component to add the earthtube to a the thermal zone. I tried to look at the energyplus documentation but when I started the simulation I found a lot of problems. Any idea around?
Best,
Angelo
hi Angelo,
I think you can use the Add_Str_ field of the simulator component by inserting a panel with the EP schedule and earthtube class as described in the I/O Reference.
Remember that a class must be declared, ends with a semicolon and has fields separated by commas.
In the absence of components you can do this.
I hope I have been helpful to you
See you soon
Dear @MassimilianoBusnelli,
Thanks for reaching out.
I was doing exactly what you said. I’ve used the Add_Str_ field but I’m struggling with the CLASS definition related ti EARTHTUBE. Any suggestions?
Thanks a lot,
Angelo
Hi,
I think it is wrong class name, for E+ 22.2, from a file of mine I have:
ZoneEarthtube,
Z20_Sala_Attesa_P0_NO, !- Zone Name
Sch_Always_1, !- Schedule Name
0.0555, !- Design Flow Rate {m3/s}
0, !- Minimum Zone Temperature when Cooling {C}
50, !- Maximum Zone Temperature when Heating {C}
1, !- Delta Temperature {deltaC}
Natural, !- Earthtube Type
75, !- Fan Pressure Rise {Pa}
1, !- Fan Total Efficiency
0.125, !- Pipe Radius {m}
0.01, !- Pipe Thickness {m}
50, !- Pipe Length {m}
200, !- Pipe Thermal Conductivity {W/m-K}
3.5, !- Pipe Depth Under Ground Surface {m}
HeavyAndDamp, !- Soil Condition
15.217967987061, !- Average Soil Surface Temperature {C}
8.446319580078, !- Amplitude of Soil Surface Temperature {deltaC}
20, !- Phase Constant of Soil Surface Temperature {days}
1, !- Constant Term Flow Coefficient
, !- Temperature Term Flow Coefficient
, !- Velocity Term Flow Coefficient
; !- Velocity Squared Term Flow Coefficient
Try…
I think it would also be better not to pass it two objects but only one with schedula and earthtube, using a concatenate of grasshopper but of this I am not sure…
Let me know!
See you soon
Massimiliano
P.s. I’ll leave you a linkdin post where I had talked about it with some graphs.
https://www.linkedin.com/posts/massimiliano-busnelli-8a02b211_energyplus-airflownetwork-ems-activity-7032353039965405186-zSRX/?utm_source=share&utm_medium=member_desktop
Dear @MassimilianoBusnelli,
Thanks a lot and congratulations for the work that you posted on Linkedin. I solved the problem but I have another doubt: which kind of output_names have you used for the simulation?
Thanks for your precious help!
Angelo
Sorry, last question! Where can I control the wind velocity? I saw your post on Linkedin and it is specified 2 m/s.
Best,
Angelo
Thank you Angelo,
in this year I have simulated three times the earthtube, for Milan in a new building, Rome on a historic building and the works will start soon, I hope, and then in Palermo, building already built and where there is possibility of monitoring (the simulated and measured data coincide a lot). In all three cases I was not using natural ventilation, but induced by a fan bottom pipe, and the velocity is the daughter of a sensitivity analysis to see which was the best, along with other parameters (diameter, depth, conductivity, etc…). Then found the suitable configuration I used ariflonetwork (which does not support erathtube) modeling an air inlet with a delocalized erv (vmc), without recovery with a specific ems script to read the earthtube annual data.
By now I’m getting the hang of these parameters!
The variables used are:
Output:Variable,
*, !- Key Value
Earth Tube Zone Inlet Air Temperature, !- Variable Name
Hourly; !- Reporting Frequency
Output:Variable,
*, !- Key Value
Earth Tube Ground Interface Temperature, !- Variable Name
Hourly; !- Reporting Frequency
Output:Variable,
*, !- Key Value
Earth Tube Zone Inlet Wet Bulb Temperature, !- Variable Name.
Hourly; !- Reporting Frequency
Output:Variable,
*, !- Key Value
Earth Tube Air Mass Flow Rate, !- Variable Name
Hourly; !- Reporting Frequency
Dear @MassimilianoBusnelli,
Really interesting! I would like to know more. Do you have publications or other documents about the projects that you mentioned before for studying them? Also can I ask you your email?
Thanks a lot,
Angelo
Sure, e-mail sent in pm.
Best
Massimiliano
