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I have some old Energy Plus idf files that I'd like to read using Eppy; however, I need the IDD file that was used to create the idfs. I have looked at the GitHub repository for the old versions of EnergyPlus and the zip files do not contain the Energy+.idd like in the latest version. Does anyone know how to obtain the IDD file for EnergyPlus 8.1.0.009??

IDD file for EnergyPlus 8.1.0.009 I have some old Energy Plus idf files that I'd like to read using Eppy; however, I nee

I have a case where I have multiple internal heat exchangers inside the same tank. This is to take a hot feed from generators such as heat pumps and solar collectors, while providing heat for both space heating and hot water. To achieve this I am connecting the stratified enhanced internal hex models of the LBNL Buildings Library in series. Please see the attached image as an example. Is this the best approach to achieve this? If not, what are the shortfalls and is there an alternative? The issue I can see is that the heat exchangers will only be present in each tank. For example, in a hypothetical scenario, where the heat exchanger enters the top of the top tank, and leaves the bottom of the bottom tank then this approach would not be suitable. In such a situation how could the existing model be modified to have multiple heat exchangers at different heights? At the moment it appears the only parameter that dictates the position of the heat exchanger is the number of heat exchanger elements in each of the tank volumes. It would be useful to be able to specify the tank volumes where the heat exchanger is present.

Edit - Following the recommendation of Michael Wetter, I added a second heat exchanger to the Storage.StratifiedEnhancedInternalHex to take into account buoyancy and conduction. here is a screenshot with the additional HEX. I then added parameters for the top and bottom height of the exchanger. Here is the additional script needed to run the component:

parameter Modelica.SIunits.Height hHex2_a
    "Height of portHex_a of the second heat exchanger, measured from tank bottom";
parameter Modelica.SIunits.Height hHex2_b
    "Height of portHex_b of the second heat exchanger, measured from tank bottom";
final parameter Integer segHex2_a = nSeg-integer(hHex2_a/segHeight)
    "Tank segment in which port a1 of the heat exchanger 2 is located in"
final parameter Integer segHex2_b = nSeg-integer(hHex2_b/segHeight)
    "Tank segment in which port b1 of the heat exchanger 2 is located in"
final parameter Modelica.SIunits.Length dHHex2 = abs(hHex2_a-hHex2_b)
    "Vertical distance between the heat exchanger 2 inlet and outlet";
final parameter Integer nSegHex2Tan=
    if segHex2_a > segHex2_b then segHex2_a-segHex2_b + 1 else segHex2_b-segHex2_a + 1
    "Number of tank segments the heat exchanger resides in";
final parameter Integer nSegHex2 = nSegHex2Tan*hexSegMult
"Number of heat exchanger segments";

for j in 0:nSegHexTan-1 loop
    for i in 1:hexSegMult loop
      connect(indTanHex1.port[j*hexSegMult+i], heaPorVol[segHex2_a + (if hHex2_a > hHex2_b then j else -j)])
end for;
  end for;

Multiple Internal Heat Exchangers for Storage Tank - Modelica I have a case where I have multiple internal heat exchange

Ok problem solved. I was able to add two internal heat exchangers to the tank and then just set parameters for separate

Thanks Michael. I noticed this but I was unsure of the connection equation: equation for j in 0:nSegHexTan-1 loop

Multiple Internal Heat Exchangers for Storage Tank - Modelica I have a case where I have multiple internal heat exchange

Multiple Internal Heat Exchangers for Storage Tank - Modelica I have a case where I have multiple internal heat exchange

@Michael_Wetter Thanks for your reply. It seems that in order to calculate the UA of the coil, the user must supply the

@Redux Thanks very much for taking the time to answer and your English was perfect ;). Yes for radiators it seems the ou

Rated heat flow of heat exchangers in the Modelica Buildings Library I am using the Modelica Buildings Library for a pro

Thanks very much for this!

I am new to energy modelling and I am curious why Open Studio does not have any templates for residential buildings? Is it that residential models are not suitable? If so why not? Surely a building simulation program should be able to handle any building; type or size.

I have looked at BeOpt and the construction choices are limited and only suited to USA methods of construction.

Thanks for this! I thought it might be something simple.

Hi, I decided to try and learn about Open Studio and Energy Plus but this is proving to be an impossible task. Whenever I build a geometry and save as both the sketchup and Open Studio model, when I close and resopen the Sketchup file, it automatically removes the open studio content. I then reopen the Open Studio file and all of the surfaces are missing and all that remains is a wireframe and the options to turn on surface rendering do not work. I have had many other problems with loading in the Open Studio model from Sketchup. I am using Windows 10.

I am wondering if there is a best practice, file management workflow that I should be following because at the moment it is causing many many problems.

Thank you for your help.