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Thank you for your quick response. For what I have been reading here, FloorSpace JS cannot convert this JSON file into a

Graphical Interface for the building geometry in EnergyPlus Hi everyone, I am currently working on the development of a

I am using "Material" for the Construction and for the MovableInsulation Classlist

Hi everyone.

I am trying to assess the performance of dynamic insulation materials, and to do so I am now using the class list SurfaceControl:MovableInsulation. In this class list, we can add or remove a certain layer of material, on the inside and/or outside of a specific opaque surface. To do so, you have to define a fractional schedule (between 0.0-1.0) that represents a fractional modifier on the thermal resistance of the material layer that you're studying (which allows to change its thermal conductivity) In order to establish a starting point (reference) to the analysis that I have been doing, I started with the case where the insulation layer is set ON. To do so, I thought it would be the same to set the material as a layer on the Construction Class List or to set it Always ON on the SurfaceControl:MovableInsulation Class List. But when I calculated the heating and cooling demand, the values were a bit different:

• Heating for the MovableInsulation Classlist: 3.1 MWh
• Heating demand, only putting the layer of insulation on the Construction Class List = 1.9 MWh

Does anyone knows the reason for that?

Thank you in advance!

3 - Finally, I broke the insulation layer on WALLS_HIGHCOND surface in two layers (each one of 5 cm).. and once more it failed to equal the number of nodes. Then I remember that from the literature review I did regarding these temperature nodes on CondFD, I saw that they also depend on the timestep of the simulation. So after having two layers, as you proposed, I tried changing the number of timesteps from 60 to 30 => Problem Solved (No Errors)

Thank you for the input @Archmage.

1 - I need to use CondFD because I need to use the temperatures inside the construction (CTF only assesses the heat balance regarding the outside and inside surface of the wall). This way I can plot the profile of the temperatures inside the wall.

2 - Moreover, I tried different combinations of the parameters in the HeatBalanceSettings:ConductionFiniteDifference object, but it always failed to equal the number of nodes in both surfaces. The thing is that I do not know what is the adequate criteria to define the changes on those parameters.

Thank you @MatthewSteen for the comment. It's kinda of an answer because the problem was solved after changing another parameter. But I will change it anyway.

Thank you for the input Archmage.

1 - I need to use CondFD because I need to use the temperatures inside the construction (CTF only assesses the heat balance regarding the outside and inside surface of the wall). This way I can plot the profile of the temperatures inside the wall.

2 - Moreover, I tried different combinations of the parameters in the HeatBalanceSettings:ConductionFiniteDifference object, but it always failed to equal the number of nodes in both surfaces. The thing is that I do not know what is the adequate criteria to define the changes on those parameters. I understand their meaning but not what I have to do to perform the changes I want to implement in terms of temperature nodes.

3 - Finally, I broke the insulation layer on WALLS_HIGHCOND surface in two layers (each one of 5 cm).. and once more it failed to equal the number of nodes. Then I remember that from the literature review I did regarding these temperature nodes on CondFD, I saw that they also depend on the timestep of the simulation. So after having two layers, as you proposed, I tried changing the number of timesteps from 60 to 30 => Problem Solved (No Errors)

Hello everyone.

My name is João Tiago Homem, and I am currently doing my master thesis on Dynamic Insulation. In the process, I am trying to simulate elements of insulation (on the walls) that offer a dynamic behavior rather than a static one, by means of:

1 - Changing its conductivity

2 - Adding/Removing a certain layer of insulation in the construction

3 - Changing its thickness

To do so, I am using EnergyManagementSystem (EMS) on EnergyPlus to achieve these changes throughout the simulation period.

Details of the model:

• BESTEST Case 600 (whereas the temperature setpoints are 20ºC and 27ºC)
• Heat Balance Algorithm: CondFD
• Timestep: 1 min

Action on EMS

For instance, I am trying to change the conductivity of the insulation of the walls, from High (0.08) to Low (0.04) whenever a certain condition is true:

• Sensors: T_in (Zone Mean Air Temperature), T_out (Site Outdoor Air Drybulb Temperature)

• Actuator: Surface, Construction State (on all walls: South, North, East and West)

• Program:

  IF (T_in > 27 && T_out < T_in) || (T_in < 20 && T_out > T_in)

    Set Ins_ConstructSouth = Walls_HighCond
    Set Ins_ConstructNorth = Walls_HighCond
    Set Ins_ConstructWest = Walls_HighCond
    Set Ins_ConstructEast = Walls_HighCond
  

  ELSE

    Set Ins_ConstructSouth = Walls_LowCond
    Set Ins_ConstructNorth = Walls_LowCond
    Set Ins_ConstructWest = Walls_LowCond
    Set Ins_ConstructEast = Walls_LowCond
  

Errors

Every time I run the simulation, I get this errors:

*** No node connection errors were found.

*** Beginning Simulation

* Severe * InitEMSControlledConstructions: EMS Construction State Actuator not valid.

* ~~~ * Construction named = WALLS_LOWCOND has number of finite difference nodes =5

* ~~~ * While construction named = WALLS_HIGHCOND has number of finite difference nodes =4

* ~~~ * This actuator is not allowed for surface name = SOUTHWALL, and the simulation continues without the override

* Severe * InitEMSControlledConstructions: EMS Construction State Actuator not valid.

* ~~~ * Construction named = WALLS_LOWCOND has number of finite difference nodes =5

* ~~~ * While construction named = WALLS_HIGHCONDhas number of finite difference nodes =4

* ~~~ * This actuator is not allowed for surface name = WESTWALL, and the simulation continues without the override

* Severe * InitEMSControlledConstructions: EMS Construction State Actuator not valid.

* ~~~ * Construction named = WALLS_LOWCOND has number of finite difference nodes =5

* ~~~ * While construction named = WALLS_HIGHCONDhas number of finite difference nodes =4

* ~~~ * This actuator is not allowed for surface name = NORTHWALL, and the simulation continues without the override

* Severe * InitEMSControlledConstructions: EMS Construction State Actuator not valid.

* ~~~ * Construction named = WALLS_LOWCOND has number of finite difference nodes =5

* ~~~ * While construction named = WALLS_HIGHCONDhas number of finite difference nodes =4

* ~~~ * This actuator is not allowed for surface name = EASTWALL, and the simulation continues without the override

If I do the same procedure changing the thickness instead of conductivity, I get the same errors. I already checked all the posts on the community regarding EMS or changeable U-value but they didn't help me finding the solution.

What do you think about this?