RE: The Konker Connection - Blog 2

jc2048 — Sun, 01 Oct 2017 22:45:34 GMT

Fascinating experiment.

I'm not very clear what's going on. As I understand it, if you have a musical instrument like a guitar or violin then much of the energy gets to the back surface via the sound post and not through the air of the cavity (but I'm in no way an expert in this, so take this as vaguely remembered stuff from reading about musical acoustics in the past). So I would think that here the energy transfer is much more efficient through the plastic material (as well as being much faster). That might suggest that you're looking at the superposition of all the multiple paths through the plastic. Those paths would vary because the boundary between water (which will damp oscillations) and air is effectively an impedance change and you'd get reflections off of it, but the relationships would be complicated because it's a 2-D structure.

One way to experiment with that and see if it has any merit at all would be to put the water on the outside rather than the inside and see if you got a similar effect.

Another experiment would be to try something other than a sinewave.

Isn't it possible to drive the transducer with a signal that has a continuous spectrum so you could look at the result varying in real time on the FFT plot rather than having to manually plot the resonances?

RE: The Konker Connection - Blog 2

mcb1 — Thu, 28 Sep 2017 10:26:13 GMT

Interesting challenge ...

One thing you may wish to check first is if the tank staddles the chassis backbone.

If it does you'll have two almost sperate chambers at lower fuel levels, and then you've got the nonlinear shape to deal with.

I would imagine it would be easier to fit a flowmeter inline.

You might need to resort to a simple capacitive sensor mounted to the cap.......

Mark