How does varying roof angle affect lift in wind

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Varying roof angles significantly impacts lift in wind, with a larger angle potentially resulting in lower lift, suggesting an optimal angle near 89 degrees. The discussion highlights the challenges of wind direction and the need for controlled conditions, while also considering the materials for model construction. Cardboard is deemed acceptable, but architectural foam board is recommended for better rigidity. Simplicity in model design is advised to avoid complications, with a focus on symmetrical house shapes. The relationship between roof pitch and usable floor area is noted, emphasizing the importance of this factor in more detailed studies.
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Hello guys!

New here. Grade 11 student.

I'm working on a project to investigate how roof angle relative to the horizontal vary with lift, according to Bernoulli's principal. The purpose is to reduce injury in storms.

Problems are:
Wind blows in all direction and I was thinking about controlling it to horizontal wind but then this might reduce the worthiness of the investigation.

I believe that the larger the angle, the lower the lift? So the optimum angle of the lowest lift would just be 89 degrees?

I'm thinking of using cardboards to make the house models, but cardboards don't reflect actual house materials?

Any suggestions would be greatly appreciated!

Thanks in advance!
 
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I wouldn't worry about cardboard not being representative but I'd probably use "Architectural foam board" instead. Easier to make a rigid model.

I think there is a danger of having too many models to build and options to test. Best keep it simple and pick a symmetrical house.

Changing the roof pitch will change the height of the ridge. It might be worth testing to see if pitch matters more than height but that's more models to build.

If the house has rooms in the roof space then changing the pitch changes the usable floor area (eg floor area with sufficient head room to stand up in). Designers can correct for this by making the house taller or bigger to keep the usable floor area constant. So this begs the question...when you change the roof pitch should you aim to keep the usable floor area constant? Personally I'd ignore this and stick to comparing houses without rooms in the roof. However if you were doing a more serious study it might be an important issue because houses that use the roof space can be smaller.
 
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