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Anonymous Poster #1

08/07/2017 5:39 AM

I am looking into the wind pressure effects on the supports for an flat panel that is inclined at 30 degrees to the horizontal.

The panel measures height(h)=1.65m by width(w)=5.305m, giving an area(A)=8.75m2. I am taking the wind direction as perpendicular to the panel and at 0 degrees to the horizontal. Therefore the vertical projected area seen by the wind is Ap=4.377m2 (projected height=0.825m). The panel has 8 support beams (2 rows of 4). In an extreme case the wind pressure is 3500N/m2 on the frame.

How would it be possible to calculate the basic forces on each support (giving their positions as a set of co-ordinates. Please see attached image diagram. Thank You.

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Guru

Join Date: Jan 2007
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#1

### Re: Forces on supports for an inclined panel under wind loading

08/07/2017 5:51 AM

What is needed is the coefficients of drag and of lift for the structure. It may have been done before: try Kempe's Engineers' Yearbook, any edition.

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Anonymous Poster #1
#3

### Re: Forces on supports for an inclined panel under wind loading

08/07/2017 6:55 AM

I have had a look at numerous text books, finding it difficult to decipher what the correct coefficients are, without modelling the structure itself and using CFD. The majority refer to the ASCE 7 handbook, but I have been told these coefficients will not be accurate as "Solar Panels do not meet the requirements for both the simplified and analytical methods. This is because solar panels are known to be susceptible to vortex shedding and wake buffeting." - this I have read a on another thread (I cannot remember where). I do not have the correct software available to conduct the correct CFD simulation.

My knowledge in this area of engineering is extremely basic, so I am only looking for a thumb suck method. Thank you for your recommendation I will take a look.

Guru

Join Date: Jan 2007
Location: In the bothy, 7 chains down the line from Dodman's Lane level crossing, in the nation formerly known as Great Britain, and now disconnecting ["brexit" - ugh] as Little England and Wales (not too sure about Wales bit, either). Kettle's on.
Posts: 27351
#2

### Re: Forces on supports for an inclined panel under wind loading

08/07/2017 6:18 AM

Another option is to simply copy the mounting arrangements used for similar, proven, structures in the vicinity. Solar panel electricity farms are a good place to look for these structures, it would appear.

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Guru

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#4

### Re: Forces On Supports For An Inclined Panel Under Wind Loading

08/07/2017 11:10 AM
Guru

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#5

### Re: Forces On Supports For An Inclined Panel Under Wind Loading

08/07/2017 4:03 PM

First, redesign to require only 4 support legs, each perpendicular to the ground...

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Anonymous Poster #1
#6

### Re: Forces On Supports For An Inclined Panel Under Wind Loading

08/08/2017 10:06 AM

Will 4 vertical supports provide more structural support for the frame, rather than those I have already designed at an angle? Thanks

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#7

### Re: Forces On Supports For An Inclined Panel Under Wind Loading

08/08/2017 11:55 AM

Refer back to (your?) Strength-of-Materials (or similar) textbook...

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