Basement to basement level?

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miguelnery
Posts: 75

Basement to basement level?

Postby miguelnery » Mon May 29, 2006 8:00 pm

Hi Andy,

I’m starting to study this building. It has 3 floors and 1 basement. The basement as 2 patios (for ventilation of technical zones) and a ramp, to access the parking area and for ventilation.
When constructing the model I tried to “realistically” put the basement at basement level. For thermal purposes maybe it’s unnecessary, as we can define the basement surfaces as “adjacent to ground”, but for visualisation purposes I thought it would be interesting.
Can you tell me if this is a correct way of constructing the model?
If yes, why grass “fulfils the patios and ramp?
Does it have implications on simulations?
Would it be better to create a component block to define site level?

Best regards,

Miguel
Attachments
layout.jpg
layout.jpg (26.05 KiB) Viewed 130444 times
visualisation.jpg
visualisation.jpg (27.55 KiB) Viewed 130444 times
miguelnery
Posts: 75

one more question

Postby miguelnery » Tue May 30, 2006 12:46 am

One more question:

It's normal that a file like this as 30MB?

best regards,

Miguel
Andy Tindale
Posts: 2669
Location: Stroud

Postby Andy Tindale » Wed May 31, 2006 2:35 am

Answering your last question first, the usual reason for extremely large file sizes is that there is some hourly or sub hourly data stored in the file. You can ensure that your file has no results stored with it by saving using the "Save without output results" File menu option, or simply by making an edit in the file. Note that saved report topics are always retained and must be deleted explicitly from the Compile report dialog.

Regarding your problems with ground level, it would help if you could send me your file (post it on this forum or send it by e-mail).

Thanks
Andy
miguelnery
Posts: 75

re:

Postby miguelnery » Wed May 31, 2006 8:41 pm

Hi Andy,

you said:
"(...)Note that saved report topics are always retained and must be deleted explicitly from the Compile report dialog."

Could you explain better this point.
I'm asking you this because I don't arrive to compile a report. I looked online help menu but couldn't arrive to any conclusions.
As you can see in the attached print screen it’s asked to select the report topics but there’s none available!

p.s: when I try to attatch the files (150kb) I recive this message:
"Sorry, you have reached your maximum Upload Quota Limit of 2 MB" :?:

I'll send the files by e-mail...

Best regards,

Miguel
Andy Tindale
Posts: 2669
Location: Stroud

Postby Andy Tindale » Thu Jun 01, 2006 12:00 am

Miguel,

Referring to your screen shot of the Compile Report dialog (sent by separate e-mail), you haven't added any report topics yet so there is no report to generate and therefore no data storage space taken up by stored report topics - no problem.

You may not have used report topics yet and this may explain your confusion. When reviewing some output data (or the visualisation screen), you may want to save the results to a report (Word document). One way to do this is to save the data as a report topic when exporting using the Export Data dialog by setting the 'Export to' data to 'Report topic'. This report topic is saved with the file and can be added to a report from the Compile Report dialog. The best way to find out is to try it!

Going back to your first problem about how best to deal with basements, the model you have sent seems to be well set up, the only problem is that the component blocks you have used to represent the ramp etc are exactly the same level as the surface used to represent the ground level and some parts of the upper surface of the component blocks show through. You can get round this problem by moving the component blocks down a fraction.

The best way to approach modelling of basements depends on what you're trying to do. In general, the only function of the component blocks in the thermal calculations is to cast shade and reflect radiation, but there will be no solar radiation below ground level anyway and so in your model your component blocks do not really serve any purpose. Also, the visualisation is not very accurate because you cannot see the ramp and other component blocks below ground level. To solve this problem, it may be worth representing the ground level using component blocks instead as you suggest. I haven't yet seen a model where this is done, but have thought many times that it would be a good way to represent different levels and slopes of the ground surface. If you are planning to do this, I would recommend raising your whole building above ground level and setting the adjacency of the basement blocks manually to 'Ground'. If you try this, please let me know how you get on.

Regarding your problem uploading files, from the message you describe, it sounds like you have a personal forum upload limit of 2 MB and perhaps you have already uploaded other files/images which take you close to your limit. I will let you know if there is a solution to this problem.

Regards
Andy
miguelnery
Posts: 75

re

Postby miguelnery » Fri Jun 02, 2006 12:43 pm

Hi Andy,

As suggested I constructed the site plan with component blocks (4 - to make the contour of the building).
One positive thing is that it just aded 1kb to the size of the file.
The other is that it works much better in visualisation mode.
I just didn't had time to make a complet simulation,
but if you want you can check the model on your computers!

P.S: I receiving the message:
"Sorry you have reached your maximum Upload Quota Limit of 2MB"
I'll send you the files by mail!!!

Best regards,

Miguel
Andy Tindale
Posts: 2669
Location: Stroud

Postby Andy Tindale » Fri Jun 02, 2006 1:39 pm

Congratulations on being the first to use component blocks for modelling the ground plane!!

I have posted an image below to help other DesignBuilder users see how this works.

Andy
Attachments
Ground slope.jpg
Image showing use of component blocks for modelling sloped ground plane
Ground slope.jpg (10.78 KiB) Viewed 130407 times
kashirachiam
Posts: 15

Postby kashirachiam » Sat Aug 12, 2006 3:25 am

Hi, Andy. I'm currently doing my final year project. How do i model the basement? Is it the way you mentioned in this topic by using the component blocks to draw the whole basement? I need your help for modelling lower ground. Thanks
Andy Tindale
Posts: 2669
Location: Stroud

Postby Andy Tindale » Wed Aug 16, 2006 3:32 pm

Hi,

The most important thing you need to know about modelling basements is that the adjacent condition for each surface in the basement which is adjacent to ground must be either 1-Auto (if the surface is below ground level, i.e. z<0) or it must be explicitly set to '3-Adjacent to ground'.

Adjacency is set on the Construction tab under Construction and Adjacency headers.

The rest of the advice on this topic is about creating nonstandard basement geometries and rendered images.

Regards
Andy
kashirachiam
Posts: 15

Postby kashirachiam » Thu Aug 17, 2006 4:03 pm

Hi Andy,
Thanks for ur help. Now i starts to model the basement.

Regards,
KashiraChiam
wholden
Posts: 5

Postby wholden » Mon May 21, 2007 6:37 pm

I was wondering if you could go into greater detail regarding the use of component blocks to model ground slopes and partially exposed basements.
What should the component blocks be made out of? How can I set the component blocks up so that in the visualization it shows grass?
Do you have any examples?
Andy Tindale
Posts: 2669
Location: Stroud

Postby Andy Tindale » Mon May 21, 2007 7:44 pm

1. In general when modelling more complex ground contact situations it is best to raise the building and basement above ground level (i.e. z>0). This ensures the in-built ground plane does not get in the way. This means that you have to set ground adjacency manually (point 3).

2. Create the ground plane using component blocks. You can set the component block material either at building level, or individually for each component block, to get the correct texture and reflection properties. Do this in Construction > Component Block data.

3. Ensure that any surfaces that are adjacent to ground have their adjacency set to reflect this on the Construction > Adjacency data at block, zone or surface level.

4. When creating the constructions and ground temperatures remember the ground construction is included by default depending on the setting at the site level (Location > Site details > Ground).

We will be putting together an example model to illustrate this soon when we have implemented a new feature where component blocks can be specifically defined as ground objects and the adjcaency of any touching surfaces is automatically defined as being adjacent to ground. Surfaces can be split into above and below ground adjacencies without the need to set up > 1 block.

Expect this in a near future beta release.

Andy
h_hassan77
Posts: 10

Basement Calibration...

Postby h_hassan77 » Mon Apr 06, 2015 7:40 pm

Hello everybody,
I've benefit too much from this discussion on building my model.
I'm now doing a calibration for a basement as shown in the picture attached.
I'm asking about the ground temperature of 2D or 3D transfer.
If there's any updates at version 4.0 of DesignBuilder??
I need to find the accurate ground temperature of the core and perimeter around the walls and floor of the basement.
Must I use the Slab Utility and make multiple iteration to get accurate ground temperature ??
Thanks in advance,
Heba
Attachments
Model.jpg
Model.jpg (93.15 KiB) Viewed 117218 times

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