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Detailed Surface Location

asked 2019-05-03 07:15:52 -0500

vitorleiteg gravatar image

updated 2019-06-05 11:55:12 -0500


I am beginner E+ user and I would appreciate some help here.

I modeled a 2 story house using designbuilder and transfered the file to energy plus. Looking at the E+ file exported from desingbuilder, I can see that the program automatically named and all my surfaces into 138 different surfaces at "BuildingSurface:Detailed" Here, every surface is divided into SunExposed, WindExposed and their X,Y and Z location.

The problem I am having now is when creating a AFN, I need to connect each external surface with external nodes and I have no idea if, for example, my "FirstFloor:Bedroom4_Wall_2_0_0" and "FirstFloor:Bedroom4_Wall_3_0_0" are connected, in this order, to the external South and East node, or if it is in opposite order.

There is any way to know the location of surfaces or how E+ name the surfaces from DesignBuilder?

Is the easiest way to do this really looking at the X,Y and Z location of each surface and then, figure out one by one where they are located?

Thank you for the help!

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answered 2019-05-03 12:25:52 -0500

Is there a reason that you have to use the "input" wind pressure coefficient feature? For a two-story house, it might be OK to use the automatic calculation of wind pressure coefficients. To do that, set the "Wind Pressure Coefficient Type" field of the "AirflowNetwork:SimulationControl" object to "SurfaceAverageCalculation". Then you don't have to input any external nodes, the code will generate them for you. If you really need to input your own coefficients, then what I have done in the past is use a viewer to figure out where the surfaces are or do it semi-automatically with a script. I was using OpenStudio for both of those, but other tools should work too. Maybe Euclid for visual or eppy for scripted?

With 138 surfaces, though, a visual process is going to be pretty tedious. Doesn't DesignBuilder had a automated way to generate the AirflowNetwork for you?

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Asked: 2019-05-03 07:15:52 -0500

Seen: 94 times

Last updated: May 03 '19