As far as I know, the movement of air molecules can result in what we call wind, sound, or heat (and maybe some other things I'm not thinking of), depending on the assumptions about its motion. Wind generally occurs when air molecules all move in a group in the same direction. Sound occurs when air molecules (or little packets of air), are locally compressed. And I believe heat moves when air molecules vibrate faster than their neighbors do, and some how that energy is moved.
This figure from "Sound and heat revolutions in phonics" in Nature helps setup what I'm curious about:
So where do we draw the dividing lines between wind, sound, and heat? How does the air "know what to do", given a certain stimulus? If I move a mass, and its position is given by a unit step function, what happens?
I understand that by Fourier Analysis, I should be exciting the air around the mass at infinite frequencies, and if this is that case, would this create wind, sound, and heat? And if so, where are the boundaries between these phenomena? Are they just related to the frequency of the motion, or something more complex like coupling or impedance matching? Would the wind, sound, and heat travel out at different speeds?