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E+ and CFD - RoomAir:TemperaturePattern:UserDefined

asked 2016-01-05 22:20:49 -0600

T.Galanos
41 ●2

updated 2016-01-06 10:24:57 -0600

__AmirRoth__

4446 ●5 ●17 http://bleedinggreenna...

Hello,

Upon reading the EnergyPlus IO reference I came across this object.

From its description I gather that this a sort of post-processing object, using results the user might have (most obvious source stated is CFD).

Unfortunately, my level on E+ scripts is begginer at best and the description provided in the reference isn't really illuminating.

From what I gather, the CFD results could be inputed in the form of a temperature stratification using a lookup table (perhaps with nonDimensionalHeight object?). But I really can't be sure.

I wonder if anyone here has had any experience using these objects to connect outside data (e.g. CFD results) with E+.

Thanks in advance.

Kind regards, Theodore.

answered 2016-01-06 10:48:23 -0600

Aaron Boranian

14250 ●86 ●24 http://bigladdersoftware.com/

The "Room Air Modeling Type" input field of the Room Air Model Type object dictates what other objects are needed to model air movement within a zone. For cases where "UserDefined" is entered in that input field, then EnergyPlus expects to reference the object you mention (RoomAir:TemperaturePattern:UserDefined). This object then references:

what zone to model air movement for
what is the availability schedule that determines when air movement occurs
what is the "pattern control schedule"

The "pattern control schedule" is really setting what type of air movement patterns occur over the course of the simulation. For example, you could reference a Constant Gradient Temperature Pattern when there's no air movement at night, then change to a Surface Mapping Temperature Pattern if you have radiant ceilings / floors operating during occupied periods. This is done by assigning a unique integer to each temperature pattern you want to model, then use the same unique integer in the "pattern control schedule".

To see this in practice, there is an example file named "UserDefinedRoomAirPatterns.idf" that has multiple instances of user-defined room air temperature patterns. You can also read over assumptions and calculation methods for user-defined room air temperature objects in the Engineering Reference document, if you want to get more into those details.

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Hello, actually i'm tring to simulate an atrium in E+ with this option (air roorm temperature (constant gradient) but i find a big diffecult to understand how can i determine the pattern control shedule, how i can determine when air movement occurs in my case study? i need help please i'm a debutante on using Enrgy plus ( sorry for my englich)