Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question
1

Check convexity, surface is non-convex? interzone surface area and same number of layers

asked 2023-04-26 21:56:16 -0600

budich's avatar

updated 2023-04-27 08:36:22 -0600

Hi,

I have several error as can be found in "Nara Tipical 42.idf" in gdrive https://drive.google.com/drive/folder...

I have some questions:

1- about convexity, How to fix this issue?

** Warning ** CheckConvexity: Zone="R TIDUR UTAMA", Surface="88ADEF" is non-convex.
**   ~~~   ** ...vertex 3 to vertex 4 to vertex 5
**   ~~~   ** ...vertex 3=[4.06,3.13,3.40]
**   ~~~   ** ...vertex 4=[4.06,3.63,3.40]
**   ~~~   ** ...vertex 5=[3.06,3.63,3.40]

2- What the mean of error interzone surface area?

** Warning ** GetSurfaceData: InterZone Surface Areas do not match as expected and might not satisfy conservation of energy:
**   ~~~   **   Area=10.4 in Surface=B5C9E7, Zone=K IIDUR 2
**   ~~~   **   Area=4.8 in Surface=U_2D01, Zone=HALL
** Warning ** GetSurfaceData: InterZone Surface Areas do not match as expected and might not satisfy conservation of energy:
**   ~~~   **   Area=5.6 in Surface=1F431C, Zone=KM WC
**   ~~~   **   Area=10.4 in Surface=B5C9E7, Zone=K IIDUR 2
** Warning ** GetSurfaceData: InterZone Surface Areas do not match as expected and might not satisfy conservation of energy:
**   ~~~   **   Area=16.0 in Surface=7F857D, Zone=HALL
**   ~~~   **   Area=25.6 in Surface=C05674, Zone=R TIDUR UTAMA

3- I have error about number of layer

** Severe  ** GetSurfaceData: Construction DASARATAP of interzone surface 559937 does not have the same number of layers as the construction INTERIOR FLOOR of adjacent surface C680B1
**   ~~~   ** ...this problem for this pair will not be reported again.

How to solve this issues.

Thank you very much regards, Budijanto Chandra

edit retag flag offensive close merge delete

1 Answer

Sort by ยป oldest newest most voted
3

answered 2023-04-27 08:57:56 -0600

Q1 CheckConvexity issue: Exposed floor "88ADEF" is certainly non-convex. The Shading Calculation Method is PolygonClipping (default), while your Solar Distribution choice is FullExteriorWithReflections. These should not trigger non-convex warnings IMHO. Maybe linked to this open issue. If you really want to get to the bottom of this, break up the floor surface into 3x distinct rectangular surfaces.

image description.


Q2 Mismatched interzone surfaces & areas: You have a first set of 3x problematic surfaces (stripped-down IDF inputs):

B5C9E7,              !- Name
Wall,                !- Surface Type
U_2D01,              !- Outside Boundary Condition Object
6.057, 6.630,  6.600
6.057, 6.630,  3.400
6.057, 9.880,  3.400
6.057, 9.880,  6.600

U_2D01,              !- Name
Wall,                !- Surface Type
B5C9E7,              !- Outside Boundary Condition Object
6.057, 8.130, 6.600
6.057, 8.130, 3.400
6.057, 6.630, 3.400
6.057, 6.630, 6.600

1F431C,              !- Name
Wall,                !- Surface Type
B5C9E7,              !- Outside Boundary Condition Object
6.057, 9.880, 6.600
6.057, 9.880, 3.400
6.057, 8.130, 3.400
6.057, 8.130, 6.600

... mismatched vertices + "B5C9E7" is referenced 2x. It looks like it should be broken into 2x wall surfaces: one facing "U_2D01", the other facing "1F431C".

Another pair of problematic surfaces:

7F857D,                  !- Name
Wall,                    !- Surface Type
C05674,                  !- Outside Boundary Condition Object
 6.057, 6.630, 6.600
 6.057, 6.630, 3.400
11.057, 6.630, 3.400
11.057, 6.630, 6.600

C05674,                  !- Name
Wall,                    !- Surface Type
7F857D,                  !- Outside Boundary Condition Object
11.057, 6.630, 6.600
11.057, 6.630, 3.400
 3.057, 6.630, 3.400
 3.057, 6.630, 6.600

... vertices don't line up. I suspect a need to break up "C05674", and an orphaned/missing surface somewhere.


Q3 Mismatched construction layers with interzone surfaces:

559937,                          !- Name
Ceiling,                         !- Surface Type
DasarAtap,                       !- Construction Name
C680B1,                          !- Outside Boundary Condition Object

C680B1,                          !- Name
Floor,                           !- Surface Type
Interior Floor,                  !- Construction Name
559937,                          !- Outside Boundary Condition Object

DasarAtap,                       !- Name
ID GypsumBoard 12 mm;            !- Outside Layer

Interior Floor,                  !- Name
ID GypsumBoard 12 mm,            !- Outside Layer
F05 Ceiling air space resistance,!- Layer 2
M15 120mm heavyweight concrete,  !- Layer 3
ID Plaster-Wall,                 !- Layer 4
ID Ceramic;                      !- Layer 5

... constructions of coupled interzone surfaces need to match (same layers, yet in reverse order if asymmetrical).

edit flag offensive delete link more

Comments

Thank you very much Denis

you are correct regards, Budijanto Chandra

budich's avatar budich  ( 2023-04-28 05:12:22 -0600 )edit

Your Answer

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

Add Answer

Question Tools

1 follower

Stats

Asked: 2023-04-26 21:56:16 -0600

Seen: 78 times

Last updated: Apr 28