@bigclivedotcom - I'm pretty sure you "disassembled" a device that kept humidity lower on the inside of the device, by using this principle. You commented on the unique manufacturing of the "solid-state" dehumidifier square patches, as I recall.
@@AppliedScience I'd known about them for a while, but shamelessly used my new-found RU-vid stardom to scrounge a module from them. (They actually sent me a few.) The biggest one that I took apart actually passed a lot of current when initially powered because it had absorbed a lot of ambient moisture. I guess that's why they specify that the power supply has to current limit and not go into hiccup mode. Another odd electrosmosis application is electronic damp courses where electrodes are implanted in a wall to drive moisture down to the ground.
@@bigclivedotcom plasterer by trade dont do it anymore but done a lot of damp wall in the past, stainless weld rods ive been told by some cowboys lol I only started watching your vids the other day some light reviews bbrought me to your channel👍nice
Anyone with a fish tank in the house can tell how crucial it would be to have a truly silent water pump. This one would fail though (unsafe due to high voltage, prone to clogging).
Dude you need to try using the philip sonicare electric toothbrush as an ultrasonic cutter I'm pretty sure it vibrates at 40 kHz! Also tell the The Thought Emporium channel which made a video cuz of your ultrasonci video to try to extract DNA or other biomolecules with it!
damn did not know TOT watches this to :) weird how people tend to watch all the same channels if they only liked one of them :)... or maybe not weird.. youtube might be part of that. anyhow i love both of the channels :)
I don't do rants on my channel, but if I did, I'd rant about the desire for authors to make their subject seem as complicated and difficult as possible. It's understandable why they do this, but doesn't serve the purpose of making knowledge accessible.
@@AppliedScience i've always seen it as an organization problem and/or a lack of artistic skill to make the paper easy on the eyes, because math is always important.
To be fair, I did a lot of modeling myself when it came to electric fields inside ionic liquids (via Nernst-Plank) and it is anything but trivial. Although the overall concept seems simple, coupling electric potential with ionic movement inside of a fluid is an incredibly nonlinear phenomenon. The PDE solver I used could barely handle even the simplest 1D cases of the problem. Then, if you choose to involve electrochemical reactions, the potential is no longer transparent and that dynamics of such a situation become even more complex, especially when your reactions couple with your ionic species whose concentrations feed back into the potential which then feeds back into the reactions. Eelctrochemistry is one area where I believe complicated mathematics is all but a necessity. My main issue is that researchers working in this field don't seem to make an effort to non-dimensionalize their variables or lump parameters making the math look messier than it actually is.
tbh, i'm lost on most everything you've said, but yeah... there should be more emphasis on making that complicated math readable for those who might actually need to use it. the same problem runs rampant with computer science. There's too much emphasis on complex formulas/expressions/etc, and next to no emphasis on making this data remotely possible to read for the vast majority of people who might have use for it. >.>
looks like you are using a Power Designs 2K-10 power supply. I worked for Power Designs back in the late '60s at their Stanford Industrial Park facility (Palo Alto, California) where the 2K-10 was produced. Brings back some fond memories. Glad to see after about 50 years it is still working.
The Power Designs supplies are excellent. I own a 2010, a 3650-S, and a 3K10B. All of them work perfectly and are in regular use on my bench, and the 3650 is older than the moon landing.
I’ve restored about a dozen of the older 2000 series supplies. The build quality in them was amazing! The main failure mode on them is the thermal switch inside the reference oven. They used a simple bimetallic switch to keep the oven at 80c. You can still buy new switches but it requires completely disassembling the oven assembly, which is difficult to do without breaking the bakelite base. I ended up designing a solid state replacement based on an op-amp, SSR and thermistor. You just drill a small hole in the oven base, feed the thermistor up and seal it in with some silicone sealant. The circuit is powered directly from the AC via a simple capacitive dropper. This keeps the oven at 80c +-0.25c, which is better than the +-3c of the original bimetallic switch. I’ve resold about 10 of these refurbished supplies on eBay and they’ve been working for 5 years now with no problems! I’ve got about 5 Power Designs supplies in my lab, my favorite being the 2020B!
I worked on this as an undergrad. Didn’t get anywhere really took me a whole year to fully grasp the mechanisms at that level and my post doc advisor would just assign me the projects that he stalled out on (which in hindsight was a bit unfair) but it was really interesting. We’d etch borosilicate glass like you do silicon to get these tiny channels. Use 20,000 V (very low currents). They had several applications proposed- though when I went back a decade later it seemed little real “big picture” progress was made (tbf I have not reviewed the papers from the group in a very long time). Specifically my post doc worked on doing electrophoresis of proteins in 2 dimensions using the chip. He and the group used positive charged micelles which moved contrary to the field, non-polar proteins would spend more time inside the Micelle and going the wrong way for the first dimension. The second dimension we’d dump in the same buffer minus SDS sufficient to break the micelles. This would make a second dimension separate on charge vs drag. (First was charge vs polarity ratio)
I was beginning to think I invented a memory of a similar method of protein separation being discussed in one of my grad school classes. I no longer think I'm going crazy!! Thanks for your story!
I remember back in the early 2000's seeing basement "waterproofing" systems being sold based upon this. Even today, I'm extremely dubious without a *lot* of retrofitting of both sides of a foundation wall.
Such flow profile distortion also exists for a flow in a packed bed. This is because the packing at the wall is less dense (due to geometry) hence the resistance to the flow is lower.
Laminar pipe flow situations. I suppose...but this is essentially a sealed system. There's not enough force being exerted fast enough to cause turbulence momentum in the pipe, so mechanical laminar flow inside a closed system. Hydraulics.
@@PacesIII i know this is old but for anyone looking at this, yes what you were aiming to describe is laminar flow. Laminar flow is related to the turbulence, if too turbulent, you can't have laminar. Also a good rule of thumb, if you are not in a pipe, assume you do not have laminar flow unless you have some very good evidence. And hydraulics is purely the study of how fluids move.
This is a beautiful demonstration with many different directions that one could go with it, to understand and to improve. This is exactly the type of inspiring open-ended demonstrations that should be standard in public schools. Bravo!
Thanks Applied Science! Again, I watch a 21 minute video and learn several things that change the way I think about the universe around me. Amazing stuff!
I use to think that Red October was obsurd, impossible non-sense as to its catapillar pump, but now I see I was wrong. Your presentation was clear, technical, and obviously sound scientifically. Thank you.
Japanese researchers did build a submarine with a magnetohydrodynamic drive. Inefficient, beyond slow and eventually, the sub ended up out of the water on static display.
> there's a lot of maths they like to throw at you because it's an academic paper man, when you're finally happy with your LaTeX setup, it's just impossible to stop writing formulas with it! :D
Very well done. I particularly appreciate your taking the time to talk about how you built the apparatus. I think this is often intimidating to would-be scientists and showing that it can be done with relatively common tools is great!
"I hope you found that interesting"... I sure did! You have a gift for explanation and a knack for finding interesting topics. Thank you for putting so much work into these videos and sharing them with us :)
I wonder what would happen if you replace the glass frit with hydrated SiO2 aerogel (before drying it), as the pores are a few nanometers the flow could be greatly enhanced.
Here is a link to a dissertation where they did just that! www.google.com/url?q=pdfs.semanticscholar.org/4f76/fcc7bf921535cd2a8aa61e53a89c767d0a7b.pdf&sa=U&ved=2ahUKEwiZ76XzitPkAhUElawKHVN1AH4QFjAAegQIARAB&usg=AOvVaw0ecdPwB0yxwVQt-4kgVPgy
Thanks for posting great videos. I started watching them in high school not understanding or being familiar with what was going on, but they were so interesting. These videos were part of my inspiration to study engineering. Now I see a lot of relevance and familiarity between your videos and my internship, especially in this video. Thanks for taking the time to make great content!
When it's only about the electric field, why not just isolate the electrodes, maybe even just with a thin layer of insulant? Wouldn't this prevent all the electrolysis-side-effects or am I missing something?
That is a good point. Some of the current flow is caused by the movement of the water. I saw this when blocking the movement and seeing a change in electrical current. I probably didn't explain (or understand it myself) fully. A true non-conductive fluid or insulated electrodes would not work.
Thanks for the explanation! :) It's probably like the naïve idea one can have to look at two electrolysis cells without providing a means of ion exchange. Definitely a very interesting topic.
From wikipedia: "The Coulomb force on a charge of magnitude q at any point in space is equal to the product of the charge and the electric field at that point" F = q E Since the force is dependent on the electric field, not the current (other than the obvious current from the flow of charged particles), theoretically I suppose you could have some kind of EO pump without additional current flow. When charging a supercapacitor for example, there is a very efficient storage of charge and energy even while pumping ions over to the electrodes. However to get continuous flow could require a peristaltic effect, with multiple capacitor plates and alternating voltages.
If the electrodes were insulated, then the charges would accumulate in a cloud near the electrode. That cloud would essentially shield the rest of the water from the field, so you wouldn't get a good field across the frit filter. When the electrodes aren't insulated, then when the charged ions reached the electrode, then the ion could take or give an electron (depending on which electrode it is), and become neutralized, preventing the accumulation of the shielding cloud of ions near the electrodes.
Can anyone help me understand how this actually moves the water, and not just the hydrogen? Maybe I'm lacking some elementary understanding, but if the only thing moving across the barrier is hydrogen, then what does it re-combine with on the other side to form water again? This is really cool, I understand the rest of the video for the most part, but I really don't grok the actual chemistry happening at the barrier!
I don't definitively know the answer, but I am guessing that it's due to the positive charge of the hydrogen cations attracting the negatively charged hydroxide anions. For example, if an imbalance of H+ and OH- occurs then they will attempt to reach equilibrium by moving together. However the H+ cations are blocked from moving back through the filter by the electric field, therefore it is the hydroxide anions that move.
There is no separation in the first place, there is only orientation going on with the hydrogen tail. A true ion does not form. The intact molecule is dragged along by it's tail. As room is made at the positive end for more water, it in turn is orientated and drug along as well. Anions or cations are not involved as in theory they are not formed, but in practice most of the energy used is for that 'side reaction' as explained about woeful efficiency near the end. Also note that there is no barrier in reality, the sintered glass media of the filter is just that much more glass surface area upon which the hydrogen tail is made and used to fuller advantage. Oil forms a similar heads and tails orientation with steel crankshafts for example only there it's the carbon head attracted to the iron molecule since carbon will readily dissolve into molten iron. Silicon loves oxygen like iron loves carbon.
@@leebarnes655 A little over my head still, but thank you - it makes more sense that there's no actual separation and it's just kinda being dragged along. My chemistry is pretty poor so I'm trying to intuit how it works
*@Mindbulletz* Yes, I didn't jump on him. Over the years I am sure I did similar things when it was convenient, but only when I or an associate was involved. About being fair, I find very few fair comments on RU-vid and sadly they are almost all written by folks with an agenda or zero knowledge about the subject. For a while I tried to offer constructive information for those folks but they either respond with another wrong statement, or if they run out of things to say they start calling someone names. You aren't allowed to be helpful on RU-vid. (Well, you are though.)
I wonder if you can enhance the separation at the walls? LIke having some different electric field there to assist? Not sure if that would mess up the overall flow field though.
could one use this design as a means to electrolyze water while minimizing thermal losses? I believe efficient electrolysis of pure water is a big topic in physics
Ive used MHD pumps for a few things, the first time was when coming across some cpu coolers made by Nanocoolers. They had a gallium tin alloy and a 0.1V at 20A converter that supplied the magnet pump. The second one was in an E beam machine that cooled the target, it used NaK as the fluid that kept the tantalum taget holder from melting. The pump you made there is essentially an electrostatic pump, one use of those is to pump low pressure gasses from one region to another in vacuum reactors for CVD. It allows a way to very precicely and evenly mix the reactants ❤
I didn't know glass created exclusion zone water. Well, I knew it did a little bit, but I guess a little bit is enough for this. So I suppose a more hydrophilic material would cause stronger pumping. Also, more light input into the active area should additionally cause stronger pumping.
Could you stack these pumps in series to generate enough pressure to build a hydraulic ram with no moving pumps? I also wonder if this is similar to how pumps work across cell membranes to selectively move molecules (but ATP powered). If glucose and oxygen could be selectively pumped out of blood plasma, then they could be combined in a fuel cell to generate electricity inside the body (that would also power the process). Generating power from blood glucose would have an enormous range of uses.
If this worked, might it be used to remove excess glucose from diabetics? Rather than pumping insulin in and creating fat, glucose levels could be measured and controlled.
This is really cool, can’t say I’ve ever seen it on video before. Love the use of the glass frit filter I also saw you supported tom’slab on patreon the other day which is really damn awesome of you so thank you!
Oh man, at 0:31 you showed the article in Popular Science, that instantly took me back over 50 years. I must have been 9 or 10 at the time and tried to replicate the experimental setup they showed on the subsequent pages of that article. I dragged my Mom all around town, through a half dozen electronics and TV repair shops looking for the exact model transformer they described in the experiment. We never found it, which might have saved me from electrocuting myself. I remember that article though. So cool. Thanks!
this seems like something that could be pretty cool in a PC watercooling loop. Depends on what kinds of pressure you can get as the cooling blocks are fairly restrictive. The pump speed seems quite low too but thats less of a problem
Another issue is the high voltage DC you'd need to run it. Can't be easy to get a couple hundred volts and water in something small enough to fit in a pc. And I doubt the flow will be enough, let alone the terrible efficiency...
@@stevenutter3614 You can get inaudible sound levels with moving components like good quality low rpm fans on a big heatsink tower without sacrificing much apart from money buying quality components.
@@TheAnoniemo High-voltage power supplies are actually pretty simple and tiny, if you don't need more than a few mA. Simple voltage multiplier circuit. Think those electric flyswatters - they run off a 9V battery, and produce around 200V from it.
@@vylbird8014 That electric flyswatter also produces tons of electrical noise and will probably fry the PC. But with the right filtering, yes. It's not that hard to build tiny high voltage power supplies that produce relatively clean output. His supply is only that big because it's a lab power supply with lots of different settings and other fun stuff that you don't need for a specialised application.
@@Electroblud Tiny power supplies for cold cathode tubes often used in decorating PC's are cheap and easily available, size of a small matchbox, and they generate a pretty respectable voltage - higher than he used in the video I believe. But I don't think they have much current capacity. I have one somewhere, but I don't have anything with which to measure it safely...
that’s what he was doing with the sensor, measuring the return current when the flow was applied. he remarked that the efficiency was like .1%, as you need loads of current to send it one way and only microamps of current come from the reverse.
Awesome explanation of osmosis. If only the H+ move across the filter and the OH- is stuck how does it recombine? Shouldn't it lower the pH on one side and raise on the other.
I was wondering something similar. Shouldn't all the space on the glass get taken up by OH- after a bunch of H+ has been pumped across and then the process stop because no more H2O can get close to the glass? Also if the OH- was going to move in any direction shouldn't it be towards the opposite of the H+ because it's attracted to the opposite plate.
Not only the H+ moves through the sintered glass, the quimical bond between H+ and OH- is not broken by the interaction with Si (it only slightly polarizes the H+ aligning the water molecule thus creating a "charged extreme to pull") so when the H passes through the filter the OH goes with it. (BTW sorry for my English).
Wow, that was cool, Ben! Thanks! I was going to ask about the Micron size of the porous glass membrane. I wonder what the results would be playing with the micron sizes and making them more homogenous?
Also, fast AC (say, +/- 2kv at a few thousand Hz) would be real interesting to monitor... if the skin effect comes into play, your flow profile will become even stranger...I don't even know where to begin to even simulate this with ANSYS, much less how to experimentally monitor the microfluidic changes, but the dynamics would be fascinating I'm sure
When you unplugged it at 4:04, I expected the current to shoot-up (instead of gradually ramping-up) since the back-pressure is instantly gone. Does the slow ramping allude to "gaining momentum" (of water-molecules) in the winding labyrinths in the glass-frit?
I'm not sure. Your observation is correct -- it would seem the flow rate would rise much quicker than the current did in the video. Someone should do a follow up with a sensitive flow meter, and plot that against current :)
Stefan Krüger would that be the maximum size of a particle that can pass or the glass particle size
5 лет назад
@@Scientificexploration i guess its the particle size that can pass - that would make more sense to specify for the use-case for filters i think.. - but it is really just a guess
I don't get it - if water particles split to OH- and H+ why doesn't OH- flow in an opposite direction to H+? how do both of these parts manage to get to the other side?
That’s why you’re more accessible than Thunderf00t: no ranting, and you’re not so full of yourself. I really appreciated the explanation of how you built the apparatus, that really brought it down to earth.
Thank you for the great discussion. I have had to explain how 1000 psig across a leak in a heat exchanger will result in fluid from the low pressure side going into the high pressure side. Next time I'll set up the salt membrane experiment and let the engineers "see" for themselves. Also, I really like seeing the way you made the experiment. Well done as always.
This is awesome! Thank you for discussing this! I was thinking the other day about those toys with colored oil that drops onto platforms, and I thought it would be really fun to build a large one that goes forever. A pump like this would be perfect, but I'll have to find immiscible fluids other than oils that can be pumped...if fact, if I could just pump the colored part and leave the clear fluid, it would be even better!
I remember back in the early 2000's, companies were selling (and still are) basement "waterproofing" systems for masonry walled foundation walls. I was and remain more than dubious for such a system in a retrofit on old work, but it likely would be quite effective on new construction. It all comes down to electrode installation and yes, the earth can be used as an electrode, but the efficiency goes even farther down. I discarded the notion for my old house, as our water issue was related to the fact that the back alley used to be a creek bed and the rears of many of our homes were literally part of the floodplain, so when it rained for extended periods, we'd start to get significant seepage of water through the concrete floor and masonry wall. I figured we'd need over 10 times the flow rate of such a device scaled up to handle it and that, plus impurities from the masonry and earth would, well, not be distilled water and chemically complicate the system by a great deal. Basically, it'd be a high electrolyte containing mixture that one's applying a high voltage to, which could turn into a double plus ungood thing in a confined space like a basement. Especially in a house that was so old that it had gas pipes (thankfully, capped off in the basement) running through the walls for old gas lights, as well as knob and tube wiring. On new work, it'd likely work well, although on new work, there'd have been a better path for water to flow provided that was away from the foundation walls and basements when the block was being constructed.
What an amazingly beautiful setup you created to demonstrate this. I have been researching the different electrical effects and unique qualities. I am going to look for the video to link a reference to. I would love to see if shining a bright light at the glass filter would change the efficiency by making the layer of hydroxyl ions thicker. I would also be fascinated to see if you pickup a current flow from the 2 electrodes across the sintered glass filter when shining a light source directly on it. Dr Gerald Pollack has shown a continuous pumping effect and also current flow to light an led powered by this layer of H2O3 "gel" layer Oh lastly have you tried the water "bridge" a layer of water across 2 beakers that will extend even to centimeter length by the high voltage potential between the 2 beakers. I am so going to have to duplicate this. Kudos on such great work.
This is very interesting. At my work we are actually trying to measure the reverse effect like you show in your video. We are interested in the voltage or current that is produced when a flow is introduced in the capillaries of a ceramic membrane. This is called streaming current or streaming potential. I never imagined the reverse was also true. Your video will help us a lot designing a system around this phenomenon!
Very nice explanation and very useful for my students in this pandemic times where there is no labs available and we as teacher need fo find attractive material for them!! Thanks for your effort to comunicate simply science!
Regarding the flow profile, I have noticed one similar to this. I put a 12" x 4ft PVC pipe on the front of a sealed 12" sub, and the airflow seemed to be focused towards the edge. Seemed to be particularly focused at 50Hz, which was the tubes' tuning. High frequency electrical signals may also show similar flow patterns.
Excellent demonstration! Would love to see more of the fluidics design/machining process - I know everyone is crazy for the 3d-printed ones these days but very I seldom see them in use.
It should be noted that I think borosilicate glass (eg Pyrex) is required. Not the much more common soda lime glass. I’m not actually sure that it wouldn’t work. I just know that borosilicate was more preferable. Not sure what glass you sintered there. You need the pore size to be comparable to the size of the double layer. We used essentially a single pore (channel etched into glass) rather than a porous filter. Your efficiency is probably so low because your pore size varies and some are probably too large. Also, probably more importantly, the pores aren’t straight so your lamellar flow is being destroyed by eddy currents. It’s why etching channels that are straight and narrow and consistent would get much better flow.
@18:30 you mention the flow profile. The EOF double layer is important. The outer layer is nearly static. It’s the inner layer that moves but it’s (like any fluid flow) very susceptible to turbulence. The efficiencies we (I say we, but again I was an undergrad when I worked here. I learned vastly more than I contributed) got were vastly higher, but the voltage was much much higher and the volumes much much lower. We worked in a partial clean room but the damn chips would always clog and be garbage. And making them by hand took dozens and dozens of hours (at least for me). We’d etch the channels in the glass than take advantage of an odd property of wet glass (borosilicate again) if it’s extremely clean and you get a single layer of totally pure water in between two perfectly flat layer of glass (which you could see quite obviously with the eye by the diffraction pattern formed) they would permanently bond - as if it were one piece. This is harder than it sounds in practice. It requires running 18.2 MOhm water over the glass plates. Having them extremely clean. A single dust particle would keep them from bonding. Oh yea, you had to put them in an oven once you got the grating to go away, to cement it. This, I think, formed a covalent bond between the siloxane (SiO3-) groups on the opposing glass surfaces. Could also have been hydrogen bonding. I can’t recall.
I wonder if a slice of wood would work instead of the fritted glass filter? Wood has tiny porous tubes (xylem/phloem tubes) that would be more organized than the randomly packed glass particles of a fritted glass filter. Might work even better? Plants, afterall, are perfectly designed for moving water up/down efficiently.
That's really cool and good explanation, what cracks me up is towels covering the bench but the perforated HV system is wide open. Electricity has so many things to explore, my problem is i am highly conductive and electricity has a thing for me even when i am being safe not to mention my output can screw with testing and does if i'm not paying attention. (i totally would be a good battery in the matrix hahaha)
