Is there a (freeware?) program to calculate 3D lift and drag for simple flying bodies, e.g. ball, cylinder, cube, wing?(adsbygoogle = window.adsbygoogle || []).push({});

There are programs to calculate lift and drag for foils (2D programs), e.g. javafoil of Martin Hepperle. Those

programs could be used to study the flow in 2D only. E.g. airflow around an infinitely long cylinder or wing

(coming perpendicular to the cylinder axis) could be calculated,

but not around a ball.

The drag force is of the form

F= Cd * SOMEAREA * rho *v **2 /2

where

Cd= drag coefficient

SOMEAREA = ... (!)

rho= density of air

v= velocity of air

The formula for lift force is the except Cd is replaced with Cl, lift coefficient.

If a symmetric foil ( eg. a NACA-foil) is rotated around its chord, one gets a 3D object, and I need to know its drag to design an object with low drag.

Eg. if circle rotates, we get a sphere. But knowing the drag coefficient for a circle does not help in calculating the

drag coefficient of a sphere, or does it?

(ok, the drag for a sphere can be found in the literature, but what about an object with resembling a drop or almost a drop?)

So, is there a 'virtual' windtunnel' to get the drag ?

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# Drag calculation in 3D, 'virtual wind tunnel'?

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