I guess that the blue shows low pressure areas because its behind the rider.
But then what is the blue area in front of the helmet?
It seems more logical that there would be a high pressure area on the small flat spot at the front of a aero helmet. suddenly the helmet designs with a single vent exactly in the middle of the flat spot with an unimpeded exhaust to the tail makes a lot of sense... Such as the catlike chrono or that original orange POC helmet. Helmets that protrude forwards could reduce that flat spot as well possibly explaining why the giro aero head and catlike drone test well
Is the diagram right or what?