Just wanted to let everyone know that I made it out to Utah today. I’ll be defending my thesis on Tuesday, so I’ve got a couple of days to put together my presentation, and polish up the thesis a bit. I’ll be out here till around the 7th or so, with the hope being that after the defense, I can take care of any needed paperwork, as well as possibly getting the final thesis revision polished and submitted to the Library. If all goes well, I may head home with everything signed off for graduation in August.
Tiff and the boys have been gone for the past two weeks being up with Tiff’s parents in Oregon, and they’ll be driving down with my sister Monday to meet up with me. It’ll be really nice to see them all again–“baching it” is so overrated.
On a thesis related note, last week I stumbled on one last piezoceramic ring while digging through an old box of receipts, and was able to get the nozzle machined to match. Mike Massee and Charles Pooley came over to help me run the last experiment. The results were mixed, but generally positive. We were able to get the jet to modulate, but the modulations appear to have damped out after a short distance:
This was with glycerin at about 500psi feed pressure, and about a 120-150V driving voltage just below the electrical resonance point. The good news is that it is very clear that there was jet modulation going on. It just would’ve been better had it broken up into droplets. In hindsight, it appears that by using a fluid as viscous as glycerin, that the viscous effects dominated the inertial ones enough to cause the jet to resmoth. Water on the other hand (as you could see from my previous post) caused an unsteady enough “steady” jet to make measurements difficult. Maybe I could’ve split the difference and tried a water-glycerin solution.
Anyhow, while it wasn’t ideal, and while it definitely points to the need for some future model refinements, it did validate part of the concept, and some of the observed behavior matched the expected trends, even if the amplitudes were off in magnitude….
Anyhow, that’s a lot of data for me to finish absorbing and wrapping into my thesis, but wish me luck!
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