Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question

Material temperature surface between walls

asked 2020-07-06 12:10:26 -0500

Alessandro Lavo's avatar

updated 2020-07-06 19:01:52 -0500

Greeting to everyone I'm currently trying to achieve a way with openstudio to obtain the temperature between material layers. i'm working on a thesis for my graduation related to the simulation of some tatched walls. The core of my thesis is to match the collected data with the results of the dinamic analisys. To do so i was already been able to simulate the behaviour of the test building achieving the correct inside surfae temperature and outside surface temperature. My tutor asked me to try, since he couldn't know if possible, to se the openstudio in order to obtain also the inside surfaces temperature, since the wall i need to test are composed of sevral layers of materials.

I'm honestly struggling in doing so, since i can't find a way with openstudio to place a sensor between those layers and flag an option to obtain results. I tried even the way of creating a measure, but even that seems not leading to any solution. [i have to admit i'm not used to create measures] I read this topic: But i didn't find it useful since i didn't quite understand how to proceed.

Thank you all for the attention and sorry for my poor explanation.

edit retag flag offensive close merge delete



If you read this post, it discusses either changing the heat balance method or manually calculating layer temperatures based on the layer's conductivity value. Does that answer your question?

Aaron Boranian's avatar Aaron Boranian  ( 2020-07-06 14:11:41 -0500 )edit

Thank you for the fast answer and sorry for my late reply. I needed almost a week to figure out how exactly use the information obtained from that post. Since i couldn't find a way to set in material the material property as suggested. After another research i found this: which i think it's the key to figure out how to implement that kind of properties into the model. If i understood well i can't do it using Openstudio,I should open the idf file and work on it using Energy plus script. Am i right?

Alessandro Lavo's avatar Alessandro Lavo  ( 2020-07-13 12:09:35 -0500 )edit

Not really, that other post is focusing on phase change materials (PCM) which can't be defined in OpenStudio -- that's why it requires the EnergyPlus script. Just changing the HeatBalanceAlgorithm in the Settings tab of OpenStudio to "ConductionFiniteDifference" should be enough to expose outputs for temperatures of surfaces between material layers within construction assemblies. This should be possible within OpenStudio without EnergyPlus scripts.

Aaron Boranian's avatar Aaron Boranian  ( 2020-07-13 12:26:07 -0500 )edit

Sorry for my late reply, I had a couple of very busy weeks. So, i managed to change the heatbalancealgorithm. My problem is that i can't really find where would be exposed the output for temperature of surfaces between material layers. I checked for it in several tab and didn't manage to find it. For what is my understanding that option would appear in the "output variables" tab. Still couldn't find it. P.s. I noticed that i can change the heatbalancealgorithm to set moisture...conductionfunction". Could that be useful to obtain a simulation about humidity and moisture between material layer?

Alessandro Lavo's avatar Alessandro Lavo  ( 2020-07-24 14:30:52 -0500 )edit

If you're only working in OpenStudio, there is an Output Variables tab that lists all possible output variables that your model can generate. You should find CondFD Surface Temperature Node <x> in that list if you are using the "ConductionFiniteDifference" heat balance algorithm.

Aaron Boranian's avatar Aaron Boranian  ( 2020-07-24 14:37:44 -0500 )edit

1 Answer

Sort by ยป oldest newest most voted

answered 2020-08-19 17:19:21 -0500

updated 2020-08-19 17:20:48 -0500

In order to review the temperature between material layers of a construction assembly, you will need to change the HeatBalanceAlgorithm in the Settings tab of OpenStudio to "ConductionFiniteDifference" (see below).

image description

In order to have OpenStudio generate the relevant output variables for temperatures of surfaces between material layers like CondFD Surface Temperature Node <x>, you will also need to add the Output:Diagnostics object, as you mentioned, to DisplayAdvanceReportVariables. This can be done in OpenStudio by downloading the Add Output Diagnostics measure from the Building Component Library aka BCL. You can search for measures on the BCL within the OpenStudio application by using the menu Components & Measures / Find Measures. You want to search for "diagnostic" in the Reporting category (see below).

image description

Once you have downloaded the measure, you apply it to your OpenStudio project in the Measures tab. Under the Library section on the right, expand the reporting group and expand the QAQC sub-group to find the Add Output Diagnostics measure. Drag and drop this into the EnergyPlus Measures section in the middle of the window (see below).

image description

Once that is assigned to the project, click on the "Add Output Diagnostics" measure title to expose the inputs you can edit for the measure on the right. You'll want to select DisplayAdvanceReportVariables using the drop-down on the right (see below).

image description

All you've done so far is allow OpenStudio to generate the CondFD Surface Temperature Node <x> output variable, so the last step is actually asking OpenStudio to generate it. Since it won't appear in OpenStudio's Output Variables tab, you'll need to use the BCL measure Add Output Variable and set the "Variable Name" input to CondFD Surface Temperature Node 1 (or whatever node number beside "1" you're interested in). If you want to generate this output for all surfaces in the model, then leave the "Key Value" input as the default asterisk (*). Otherwise, enter the name of the specific surface for the "Key Value" (see below).

image description

You should then run a simulation, and if it finishes successfully you can plot surface node temperatures in DView (see below).

image description

edit flag offensive delete link more

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools


Asked: 2020-07-06 12:10:26 -0500

Seen: 379 times

Last updated: Aug 19 '20