I’m modelling a greenhouse where an aluminised insulation screen covers the entire roof (internally) whenever internal temperature falls below 16℃ to protect the crops. Does anybody know if it is possible to model this in EP?
It is possible to use the EMS actuator object for Surface Construction State and EMS Construction Index Variable object, where you can apply conditions where a surface will change the construction assembly it references. There is an example in the EMS Application guide about how to change the construction of a window to account for thermochromic technology that changes window transmittance in response to changes in window surface temperature. The application is close to what you want to do, but should only require creation of two Construction objects: one for the greenhouse roof with the aluminised insulation screen and one for the greenhouse roof without the insulation. If you want to control according to the greenhouse internal temperature, you will also need to reference the zone's mean air temperature as an EMS Sensor object so that it can be used as an EMS variable. Finally, you'll want to use an EMS Program object to tell EnergyPlus the conditions for the changes you want to make to the model and an EMS Program Calling Manager object to tell EnergyPlus when to execute the EMS program during the simulation.
Thanks a lot Aaron for your comprehensive reply.
You're welcome @Mroy! If you feel the answer addresses your question, click on the check circle next to it so that other users know it's a good answer.
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