Hi Pierre:
OK, well, we’re back to the theme of perpetual newbies, who, no matter how long they may go on about wind energy in some form, never learn the basics of the art.
The fact is, even though air is in fact “compressible”, for wind energy, and, I think most typical subsonic aerodynamic research, the approximation of “incompressible” is seen as sufficient, as a simplifying assumption, making most research way cheaper and easier, yet yielding results that are “good enough”.
The reason is, in such applications as wind turbine blades or airplane wings for general aviation, the amount of compression of the air is so small, that it is OK to completely ignore it, for most applications.
The bottom line was also the fact that in most cases, the exact choice of airfoils often doesn’t even matter that much, and even given that reality, after a while I could not only predict the performance characteristics of an airfoil by just looking at it, but also fabricate them from scratch by whether they just “looked right”. This is pretty common once you get used to working in the field of aerodynamics. 
Hi Doug,
Air pressure and comfort study of the high-speed train passing through the subway station
Highlights
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Numerical model of the train passing through tunnel and station is established.
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The pressure variation of the train under different conditions is investigated.
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The comfort of passengers under different air tightness is analyzed.
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A series of parameters related to train safety and comfort are given.
If a (water) kite takes a lot of cross-sectional surface, the measurements might be distorted, as for a train.
Things are perhaps different for marine turbines which take a relatively smaller cross-sectional surface, water passing through.
Well, it’s been years since I’ve examined it, but everything I’ve been exposed to as far as CFD for wind turbines is done on the basis of incompressible flow, as an approximation. Making such simplifying assumptions is common when calculating complex subjects.
I can also tell you my experience with blades from a major producer, designed with intensive CFD guidance: Blades I fabricated by just making them look right slightly outperformed the factory blades.
Of course that is only after years of discussions with such knowledgeable people about optimizing blades.
Anyway, the main determining factor is swept area, based on diameter. In general, any reasonable airfoil will do the job. Of course there are optimized airfoils for certain use cases, such as stall-controlled wind turbines that use airfoils designed to stall easily, which would normally be a bad thing, but for stall-controlled turbines is essential. Of course the average reader here will ask “Stall-controlled - what’s that?” Then we’re back to the perpetual newbies and trying to explain the importance of overspeed protection. “Overspeed protection - what’s that?” or “We’ll just shut it down for strong winds”… (and miss your most productive days).