3 ms·
I just tried this with a mug of coffee in an ultrasonic cleaner. Left it running for about 5 minutes with room temp water and ground coffee in the mug. Compare
by bitdivision 2y ago
I just tried this with a mug of coffee in an ultrasonic cleaner. Left it running for about 5 minutes with room temp water and ground coffee in the mug.
Compared afterwards to a mug left outside the ultrasonic cleaner. There was definitely more extraction in the ultrasonic cleaner, though the coffee was still fairly weak. Likely needs more time given that they are using a custom horn etc.
- ano-ther 2y agoThanks for the test. They also use 100W of ultrasonic power: https://www.sciencedirect.com/science/article/pii/S1350417724001330 https://www.sciencedirect.com/science/article/pii/S135041772... and a cursory search says this is the domain of more expensive ultrasonic cleaners (> 100$).
- bitdivision 2y agoTrue, the one I have was a China special, but does say 60W.
- moffkalast 2y agoSupposedly ultrasonic cleaners use 15-400 khz, and DML audio exciter drivers go to 17-20 khz, so you could theoretically grab a few of those for under $100 and have at it with a sine generator.
- bitdivision 2y agoThe transducers are fairly cheap from China [0]. I've thought about making a high powered bath before but never pulled the trigger. 0: https://www.aliexpress.com/w/wholesale-ultrasound-transducer.html?spm=a2g0o.home.search.0 https://www.aliexpress.com/w/wholesale-ultrasound-transducer...
- moffkalast 2y agoAh right, yeah those would be perfect.
- moffkalast 2y agoI would imagine there needs to be direct coupling between the transducer and the container holding the coffee, the water layer likely doesn't transfer nearly as much. Probably best to just get a stainless cup, glue the transducer(s) to it and let it rip.
- jarvist 2y agoWater is incredibly efficient at transmitting sound.
- moffkalast 2y agoDoesn't mean the cup is any good at absorbing it.
- jarvist 2y agoThe mug will attenuate almost all the signal. Maybe try with a disposable plastic cup?
- bitdivision 2y agoI'll try it another day, the cleaner is packed away now. Perhaps a ziplock bag would work well.