- #36
russ_watters
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The diagram only tracks one set of interactions. If you're inducing a wave with a piston, the piston has to retract to complete the wave, otherwise you are just shoving the air out of the tube. If you make a wave, the average velocity is 0.1+(-0.1)=0 (and a cajillion other values that sum to 0).Freixas said:This doesn't sound right. Now 0.1 m/s is not much speed, but it could be 50 m/s and now we're getting wavefronts traveling at significantly different speeds.
Am I wrong? Did I miss something?
However, you can do that if you want; with a reciprocating pump, a fan starting, a valve opening. In that case you simply end up with a positive flow rate(velocity).