Wind pressure force for complex profiles ?

AI Thread Summary
The discussion focuses on calculating wind pressure forces on complex 3D shapes, particularly those tilted at angles like 45 degrees. Key references include ISO 4302, which outlines basic wind load calculations using the formula F = A * p * Cf, where A is the effective frontal area, p is wind pressure, and Cf is the force coefficient. Participants highlight the need for more sophisticated methods beyond simple calculations, suggesting simulations for detailed analysis. The conversation emphasizes understanding the full force exerted by wind, not just the force in the wind's direction, and notes that coefficients can be adjusted for wind at angles. Accurate wind load assessments are crucial for designing structures to withstand strong winds.
Aleksej
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How to calculate the force of wind pressure, for example for the surface tilted at 45 degrees?

I need to find some serious work related to the wind pressure force calculated for different 3D shapes affected by wind from different angles.

Can somebody recommend me the good names, keywords and sites for this?
 
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There are some standards that are based on simple calculations, for instance ISO 4302. If you need something more sofisticated, I don't know if there are other ways of doing it than simulations.

I guess that "wind load" is the keyword here.
 
Thank you very much, I will try to use it but they consider "force in the direction of the wind", I need more something like full force.
 
Aleksej said:
Thank you very much, I will try to use it but they consider "force in the direction of the wind", I need more something like full force.
If you're talking about the ISO standard, they are considering full force. That's the point of the exercise: figuring out the maximum load on a structure in order to design it such that it can resist in strong winds.
 
You see what they write:

---------

4 Wind load calculations

For most complete and part structures, and individual members used in crane structures, the wind load, F, in kiloNewtons, is calculated from the formula

F = A * p * Cf

A is the effective frontal area of the part under consideration, in square metres, i.e. the solid area projection on to a plane perpendicular to the wind direction;

p is the wind pressure corresponding to appropriate design condition, in kiloNewtons per square metre;

Cf is the force coefficient in the direction of the wind, for the part under consideration (see clause 5).

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Their coefficient is "in the direction of the wind".
 
Aleksej said:
Their coefficient is "in the direction of the wind".
Yes, the force coefficient, which depends on the geometry of the beams, is calculated for face-on load. Then, in section 5.4, the equation is modified to take into account wind at an angle:
$$
F = A p C_\mathrm{f} \sin^2 \theta
$$
 
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