Re: [EnergyPlus_Support] Maximum number of objects per branch / per loop in Energy plus

Dear Pauline,

I have not made this particular change myself, but you should look at the:

C:\EnergyPlusV8-6-0\Energy+.idd file, which is a text file that assigns limits to each E+ object.

Te Branch object shows up like this in v8.6:

Branch,

Â Â Â Â \extensible:4 Just duplicate last 4 fields and comments (changing numbering, please)

Â Â Â Â \memo List components on the branch in simulation and connection order

Â Â Â Â \memo Note: this should NOT include splitters or mixers which define

Â Â Â Â \memo endpoints of branches

Â Â A1, Â \field Name

Â Â Â Â \required-field

Â Â Â Â \reference Branches

Â Â A2, \field Pressure Drop Curve Name

Â Â Â Â \type object-list

Â Â Â Â \object-list PressureDropCurves

Â Â Â Â \object-list ExponentCurves

Â Â Â Â \object-list LinearOrQuadraticCurves

Â Â Â Â \object-list CubicCurves

Â Â Â Â \object-list UniVariateTables

Â Â Â Â \note Optional field to include this branch in plant pressure drop calculations

Â Â Â Â \note This field is only relevant for branches in PlantLoops and CondenserLoops

Â Â Â Â \note Air loops do not account for pressure drop using this field

Â Â Â Â \note Valid curve types are: Curve:Functional:PressureDrop or

Â Â Â Â \note one of Curve:{Linear,Quadratic,Cubic,Exponent}')

Â Â A3, \field Component 1 Object Type

Â Â Â Â \begin-extensible

Â Â Â Â \required-field

Â Â A4, \field Component 1 Name

Â Â Â Â \required-field

Â Â A5, \field Component 1 Inlet Node Name

Â Â Â Â \required-field

Â Â Â Â \type node

Â Â A6, \field Component 1 Outlet Node Name

Â Â Â Â \required-field

Â Â Â Â \type node

Â Â A7, \field Component 2 Object Type

Â Â A8, \field Component 2 Name

Â Â A9,\field Component 2 Inlet Node Name

Â Â Â Â \type node

Â Â A10, \field Component 2 Outlet Node Name

Â Â Â Â \type node

Â Â A11, \field Component 3 Object Type

Â Â A12, \field Component 3 Name

Â Â A13, \field Component 3 Inlet Node Name

Â Â Â Â \type node

Â Â A14, \field Component 3 Outlet Node Name

Â Â Â Â \type node

Â Â A15, \field Component 4 Object Type

Â Â A16, \field Component 4 Name

Â Â A17, \field Component 4 Inlet Node Name

Â Â Â Â \type node

Â Â A18, \field Component 4 Outlet Node Name

Â Â Â Â \type node

etc. for 11 components

Note that it is "extensible", so you are allowed to add more components by following the format of the previous components carefully.

I recommend that you save the original version as something like "Energy+.iddold" before changing the file.

On Mon, Jan 16, 2017 at 9:06 AM, pauline.couvrat@xxxxxx [EnergyPlus_Support] <EnergyPlus_Support@xxxxxxxxxxxxxxx> wrote:

Â

Hello everyone,

I have an airloopHVAC to modelise with A LOT of objects in it. I need to put all these objects in series (and not in parallel).Â Â I did put a lot of elements in my loop, but now, if I add one, the simulation crashes, as if I had reached a limit.....Â (for example I have already two heat exchanger in the branch and I try to add a third one; or else; it's not the type of object that seems to be the problem but really the total number of objects in the branch).
So it seems to me that there is a limit regarding the number of objects per branch or per loop, but I can't find any information regarding this.
I tried to get around this limit, by adding a part of the objects I had to add in the OutdoorAirSystem of my airloop branch; it works, but it seems to be limited too: if I have 8 objects in the OutdoorAirSystem it's ok, if I add a ninth element, it crashes too....
Does someone has information regarding the limit of number of objects per branch or per airloop? is it real and what is the limit?Â Are there differences regarding this issue between the different versions of Energy plus (8.0 or 8.6?)
Does someone has tips to get around this issue and add more objects?Â

Thank you,
Pauline.

James V Dirkes II, PE, BEMP, LEED AP
CEO/President
The Building Performance Team Inc.
1631 Acacia Dr, GR, Mi 49504

Direct: 616.450.8653
jim@xxxxxxxxxxxxxxxxxxxxxxxxxxx

Website l Â LinkedInÂ | May 2016 ASHRAE Journal article on energy modeling

...and the more I considered Christianity, the more I found that while it had established a rule and order, the chief aim of that order was to give room for good things to run wild.