I recommend removing the turbine housing walls complete and replacing them with 4 corner legs instead (and mounts to hold the nozzels). That way the water could exhaust out into the larger enclosure and drain without chance of splashback.
Why not have the size of the housing another half as large to prevent splashback from being able to reach the pelton turbine wheel. If it still has the energy to do that, have vanes fitted to the inside of the housing - fitted at an angle to "capture" the exiting water - preventing the return of the cplashback. Think of internal baffles allowing the water to enter but not be able to reflect back. One could even have them angled to deflect the exiting water downwards as a means of preventing splashback
Yes I was just thinking the same. The turbine housing should be a bit larger and with the walls tilted downwads or even curved round an downwards like a house roof to bend the splashing downwards. I think actually a stainless steel baking bowl would do it. Though ruin the view we can see you filmed throig today in slow-mo. Thank you for your series. Learning a lot.
I agree bigger housing you can get 3/4 thick plexi would be superior to plywood resin/fiberglass too boat epoxy is very strong also he could turn side ways for horizontal different jet position too so that water is moving in one direction or dual stream focused in a reverse V so both streams are focused I dont see single side causing uneven bearing load because water is a solid and its fairly constant there is also the possibility of one jet followed by the other that way splash back is occurring later if you can imagine a clock and say the jet pushes it from 5 oclock the water leaves the spoons at about 12
Then add a smaller turbine at the bottom of the spout to try and harvest some of that waste energy. And as water falls down the cone it should accelerate.
If you make this cone long enough, most of the centrifugal forces will be directed downwards by the acceleration of falling down. Jet the falling water onto a small very low weight turbine that is perpendicular so that the water wheel catches the water as it falls. I'm not sure what the speed of the water is in the turbine, but it seems pretty close to terminal velocity, so we probably wouldn't even have to be that big a cone. the biggest thing would be making sure the water flows freely from the spout without pooling up in the bottom of the cone. messing around with the angle of the cone can help with any turbulence.
@Eric Vercruyssen Because shape of the housing is not the isue here. It looks to me that the turbine is spining too fast, he should use turbine with smaller diameter or conect it with generator able to get more power out of it at this RPMs. This type of turbine have best performance when blades are moving with half of the speed of the water in the jet. With half of the speed the water gonna hit the blade and transfer almost all of its kinetic energy into turbine blades. Wrong direction of the jet can also be part of the problem.
Motor sounds like it’s struggling at first... .....Pulls the 3 phase wires out of a puddle. Motor speeds up and runs more efficiently.... “That was weird! It was acting like there was a short. I don’t know what thats was about...”
Two ideas: 1. Can you reverse the direction of the round insert so the seam would catch the water and take it out of the housing? 2. Can you make a cone so that the water hits and goes down as soon as it hits?
Yeah the cone - I had in mind. And a round enclosure with tight tolerances, but I don't think this type of spoons are made for that design, and will cause water drag when too tight.
I had the same idea. Doesn't even need to be a cone. Could be pyramid and still work a lot better than what he has. As long as it's moving more of the water down and out
Given what I've seen in commercial turbines, your enclosure needs to be 2x that size and round, with the nozzles sticking out close to the wheels. Round should be good, but ideally it'd be slightly conical, so the water is directed down once it's flung off the turbine. You need enough distance for the water to miss the spoons as it reflects back off the wall.
At 9:12 it appears that the water circulating is hitting the jet, thus causing it to loose direction. Perhaps the permanent solution should indeed be a flattened down facing cone with little windows to let water escape just before the jets. Anyway, great job!
Would have thought a bigger box would help stop the splashback. Also you should try and get some splash mud flaps. You'll see them on trucks (we do here in Australia), and look like the hook side of Velcro, except it's about 1/2 cm long. They basically stop water splash back.
LOVE THIS CHANNEL. The fact you are willing to try different ideas is what I love about this channel. I am a subscriber by the way. A simple solution you mentioned, to cut the turbulence is exhaust points for the excessive water at the corners. You have a vortex but excess water splashing back. Having a large hole on the corner would allow the water to spin, and then exit the main chamber. Keep up the great work,
The high speed is SO PRETTY! I love it! Watching the droplets move. Epic. Thanks for testing taking the corners out. Had a feeling youd gain some efficiency. You could poke holes in the circular housing to let water through as it spins but not enough holes that it could come back. Let it drip down the corners essentially. The other thing you could do is make it thinner at the top than the bottom to encourage the water to go downwards.
3:30 very interesting to see that the reflected water jet changes direction as RPM increases. at low RPM it's directed almost backwards, then there's a point (i assume it's where turbine linear velocity reaches 1/2 of the jet velocity) the jet is dispersed sideways, and then it's just slightly redirected. it also means that at low RPM it transfers the most impulse from the beam to the wheel.
If the RPM is lower than a peripheral velocity of 1/2 of the jet velocity, there will be a higher torque on the shaft, but still a lower power output as some kinetic energy is returned to the water as it's thrown back. The point of best efficiency and power output is in fact when the peripheral velocity is 1/2 of the jet. Of course, if he didn't match up the generator to the turbine, the point of highest total electrical power output might be different from the optimal rpm of the turbine due to the efficiency curve of the generator.
@@jonsen2k i wonder if instead of regulating nozzle flow by a valve, it might be better to regulate it by changing nozzle width. this way one could find the sweet spot for jet velocity when it's neither reflected forward nor backward on optimal generator rpm.
Idea: What if instead of a case housing you would use a frame just to hold and align everything but allow water to escape away from the spoons so it causes no windage?
Sounds good. I would also like to see that. A painted metal frame to hold the jets in place would let the water splash away further. The turbine can rest/attach on top of the frame and can also let you remove the turbine separate from the jets. Metal plates can be mounted on each side to direct the splash away from the turbine (out towards the corners). Maybe it gets a bit messy, so the jets and piping could be covered with some splash protection instead. The round enclosure does seem smoother, but the space is tighter. So a bit of give and take there I guess. Really like your experiments :)
@@WhiskeyGulf71 Yes, but you can still have the acrylic plate connected to the turbine, so should be the same. Adding a metal edge would make it stronger, and then it can rest on the bottom frame. Could also add a shroud around the top center to prevent water from getting there. Noticed some rust on one of the valves, but the rest seems to be more corrosion and splash resistant. Would be interesting to see how the shaft and bearings are doing now.. May be 3 points of contact in horizontal position. Might be less friction if it was vertical. And if it was not using bearings, but tight fit and oil. (A metal alloy sleeve used as sacrificial material). Bearings definitely dont like water, and are less durable. So you have a really good point keeping water out of there :) I'll have to re-watch how the turbine was put together now :)
So the motor is on top of the acrylic, and should not get splashed much. Would need to either extend the acrylic or make walls on the top side if the cage is to be skipped. The bolt in the bottom is fixed, so no friction there. But then it's hanging on the top instead. But not much weight, so might not matter a lot which way it is installed. Probably simpler to just replace bearings now and then. :)
Maybe you could build a naked frame around the spoon side of turbine, and keep the perspex shield to protect the alternator section. Bit like a four leg table design ,and incorporate a upright to strap wiring to away from water. Also weld some sheet plate ,just in areas where jets come in. Then this way less water is splashing back onto spoons ??
Great video. I hope you are paying really close attention to the transition from your reinforced hosing thru your ball valve and thru your jet. You are effectively accelerating your water and any losses there will be easily quantified. You don't want to be having turbulence from square edges steep tapers etc. Just think what a water monitor looks like. I also suspect that this would work better in a horizontal axis. In this axis the water from the upper set of "cups" must drop thru the lower set of cups. You want the water hitting the cups, expending its kinetic energy to the cups and then getting a straight shot out of the way. You could simply use two parallel jets mounted to achieve the desired impact. It may also be desirable to put the ball valves some distance upstream from the nozzles to minimise their affect on your nozzles. An effective way of stopping water getting to an alternator without huge friction losses is to put a disc on either side of "barrier. The water can not pass the spinning discs because it is simply thrown off. Kind of like a continuous labyrinth seal. No physical contact to anything, just a tiny bit of windage.
*@Joe Malovich* eg: 9:40 -ish. Maybe you can build a kind of protective cover for the jet-beam "upstream" inside the turbine, so the used water that goes around the edge doesn't cover the beam & both re-direct the beam & "steals" momentum from the beam.
Hey Joe! As many people said, a bigger housing diameter would prevent water from splashing back and hitting the jet. From my experience in a company manufacturing small hydro (50-500 kW) turbines, vertical axis Peltons always have a big housing, let's take a 0.6 m wheel diameter, the housing would be around 2 m (3 times bigger!). Anyway this is a very small turbine, so probably a housing diameter twice the wheel should be a good compromise. One last "humble" opinion about the wheel: the amount of water combined with the head of your turbine would need bigger spoons. I say so because the jet seems to be quite big compared to the spoon size, which means the turbine is less efficient (water leaves the spoon with very high turbulence) and also more splashing all around. I hope this may help. Thanks for your videos and for sharing your experience.
As you said getting the water away from the alternator is key so with the round housing I would make some openings (semi circle cuts) along the top every few inches so the water can escape once it has hit the rotors and doesn’t splash back. also maybe adding some water deflectors before the nozzles on the round housing to send the water up or down so the “spent” water that has already hit the turbine fins doesn’t hit the new water coming in making the stream turbulent.
If you cut a hole in the liner where the water is splashing back at 4:31. The water would (hopefully) get trapped in the corner behind the liner and drop away
As many have commented already, I would like to see a total open design. This can be achieved with a fairly large metal frame and acrylic top. This will cause more water in your pit, yet it may solve many problems, I suspect that you could see 10% or more improvement. It should be pretty simple to do.
I was going to say the same thing, but thought I would read through what others had already said. Possibly angle the holes so they would help direct the splashing water out.
I wonder if an inverted bowl enclosure might be useful? At the angle of the jet and spray off the spoons, the side of the bowl at that point would encourage the splashback, and really any water which is ejected from the turbine as it spins, to be forced downwards and away, out of the enclosure.
Interesting. Have you thought about perforating or slotting the circular baffle?, just enough barrier to prevent the splashing back but thick enough to slow the water down and reduce the splashes from the square edges. This is all about impedance matching - ideally, it should look like there is no enclosure at all. I don't know if any of what I'm saying will really help, but that's what I'd be tempted to try
Joe. Place a strip inside the cylinder spiraling downwards. When the water deflects, it will be channeled downward. I would start with one but 2 or more may work better,
i think just havving a big circular housing with more space for water to escape rather then a box, then it would even be easier to make out of stainless?
What about adding a few corkscrewed strips inside your round insert to direct the water downwards as soon as it hits the surface? You’d probably only need one strip per side, a long gradual decline so it doesn’t slow the water too much?
Drill holes in axial alignment with the turbine spoons in the round liner. This would allow the water into the gap between the round and square housing segments and likely eliminate all splash-back...
Joe, do you want the design 'rules' or guides for the parameters for the housings on vertical and horizontal Pelton wheels? Should have them lying around from my thesis somewhere. Might help you to sort something that works as best as it can.
For those that are interested, all of this is from Pelton Turbines, Zhang 2016 and checked with a fair few other sources. The casing design is very different if the turbine is vertical or horizontal, the horizontal casing that Joe is using here should be completely open underneath the turbine while being close up to the buckets on the top. The gap between the buckets going up vertically should be 0.3 turbine diameter, extending out to 0.6 turbine diameter when the curve is in line with the plane of rotation. After that, it can drop vertically to the drain. The circular casing Joe added prevent windage, but to be ideal, it needs to have a curve added so that it blends into the top of the housing, and then curves down to meet the runner, with a larger gap at the tip of the turbine buckets. Not an easy thing to make without casting something or getting more creative than the gains that this will likely offer.
@@JoeMalovichI undertand that Turgo might be a solution to the splashing but the disadvantage of turgo is that the force of the jet is not aligned with the rotation and therefore I would assume angular losses.
Hi Joe love and warm regards from India, I feel you must make a involute just big to fit the pelton wheel, you can visualise it as a "C" that's like half cut square, going around the pelton wheel will reduce the drag form a more uniform water flow over the wheel, also I recommend to add 4 more nozzles so a total of six nozzles with a enclosed involute specially made that just fits pelton wheel, should surely increase its efficiency, lovely work and a great design, great effort in that biting cold Joe, God bless and keep the good work going.
I think around housing that folds completely around the peloton wheel with minimal clearance (like 2-3 mm) would be the best solution. This way the air moves basically at the same speed as the turbine and will have very low turbulence. To get the water out you create two whole at the top and the bottom behind the the jet nozzle, which match the spray back from the nozzle. To avoid that water is falling back in the upper hole (by a different nozzle), you need some kind funnel leading outwards.
there is actually an ideal gap between the spoons and your outer wall. look into fan ducting, it's the same idea. but you really only want like 0.25-0.5" of clearance with the spoons, and you should probably drop your headspace above the spoons to about the same. what's the id you need, because I may be able to help you out with some stainless tube that's the right size
Awesome videos man. I've always loved your channel since you where at your old house. The new house is even better and to me although it's not always providing water it's still a awesome property for hydro. My next house when i look for one will have to have some kind of spring or water higher in elevation so I can make one. I already have 1.1kw solar system I built.
Greetings from Chapel Hill NC 🤘. I've been following you for some time now. Apologies for not subscribing sooner. You're working projects are fantastic.
Can you run more small nozzles to use up the full flow rate? Does that give a proportionately higher power output? Long nozzle tubes with venturi inlets from the larger pipe will exit in a laminar flow. A fixed stator will direct the discharge water away from the rotor.
just before you mentioned a possible short, I noticed that the connectors for the 3 wires appeared to be in the water. That would tend to cause a shirt
Quentin Clark has a point. I remember looking at MWh pelton wheel housings, of the ones I've seen the shaft was horizontal, the nozzle came in from the side at the lower side of the wheel. Loads of space for the water to deflect and down and out away from the wheel. Not really applicable here but with the circular housing looks like the right idea, but it looks like it needs to be alot larger for it to work to keep windage away from the wheel.
you need to take the insert and flare it out so it's wider on the bottom than it is on the top. that will keep water to the outside insert and direct it downward naturally
I wonder if you added "guides" to the circular edge to guide water down? sorta like what you see on the barrel of a gun...? to direct water right down as fast as possible
The perforated type would be a good way to go. The type we use down here for French Drains. www.metalculvertpipe.com/img/perforated-metal-culvert-pipe1.jpg
What if you make the water guard like the drum of a washing machine? Have it full of holes to let the water be forced out from the turbine and run down the back away from the spoons. There is two way of doing this the other is a little harder to explain but will work too.
You have a large concrete block enclosure, why not make your circular box much larger to allow the water to fall away from the turbine instead of splashing back. Leave nozzle positions in same place.
Looks like just about anything to get the 'spent' water away would be helpful, gap in the top, holes/slots/diverter vanes. Perhaps even a stainless steel blower wheel (I.e. what gets use in HVAC blowers) with the vanes in the right direction could be an off-the-shelf solution that could be modified to work for your final enclosure? Just something to catch the water, move it away from the wheel to get it into an outer portion of the enclosure where the water can drop down to the drain.
Have you thought about adding louvers to the circumference of the circular housing acting as sort of a one way valve taking the water away? Similar to a windage tray controlling oil inside of a performance engine.
Look into windage trays for engines. They have slots so the oil can escape easily into the pan and get out of the crank case. Something similar here would let the water escape from the wheel and help keep it from splashing back.
Wouldn't making the box longer, at the face the nozzle is shooting along, help to mitigate the splash? More of a rectangle rather than a square. I would also make the box taller, so there is more space between the turbine and the walls. It should allow the high speed water to lose some momentum.
Joe, I just recently discovered your videos and what you are doing I think is really cool. I'm sure you have researched this topic at length but I build racing engines and understand fluid flow. I wondered what larger more commercial water turbine designs looked like and I found this website with a 10KW turbine. I wonder if you incorporated a similar turbine housing design if your water flow turbulence would increase the efficiency. I think this design (on the website) incorporates a down draft turbine blade design but the fact that the housing is both cylindrical and cone shaped allowed for the water pressure to dissipate and fall away. I wonder since your Pelton wheel requires more of a direct side impact with water flow, if you created a half donut shaped upper housing for the water to reflect off of and help smooth the turbulence of the squarish corners between your plexiglass and the cylinder. I imagine if you want to keep the upper lid visible, you could use clear casting resin to make a semi transparent "half-donut". Here is the site I found, have a look. www.micro-hydro-power.com/Micro-Hydro-Turbine-Power-Dual-Nozzle-XJ30-10DCTF4_6-Z.htm
I just had a thought -- maybe if you made the housing conical so that it gets larger as it goes down to deflect the water downward it would reduce splashback. Like how a bullet trap is angled down instead of flat to prevent backward ricochet.
What if there were guides in the circular liner to slowly direct the downward, a spiral that directs the excess water downward? Maybe you can direct the excess water so the water goes under the next jet.
You could buy some thick *plastic* cutting boards (a.k.a. butcher blocks) for housing material instead of stainless. I'm not sure how they compare based on price, but neither one would warp from moisture.
Think of it like a rain tire. Shed the water by using radial cuts that direct water outside the circular baffle. I would direct the jet toward the spoon as usual and add a baffle just at the initial impact spot(direct the initial), then after do the radial openings that direct water away.
Hi Make a new enclosure using the same lid but with 4 new sides at steep angles like a pyramid or tank armour to angle the overspray down to the ground. You would need to make nozzle extensions though. Another idea is to cut strategicly placed vents in your baffle, sort of like the vents in a windage tray in a crank case of a motor.
whether a round or square housing- After the water hits the paddles divergence needs to take place. Find out where the water goes after the paddles, trap it and get it out of the housing eliminating its ability to slow forward movement of the wheel.
Maybe add some small vanes in the inside of the drum, angled 45° down? As the vortex gets going, the vanes should help the water become forced down and out
Larger, round housing, walls angled so that water hitting them is directed down. Something I'd try is shaped pieces to turn water back in the rotation direction after it flings off the spoons. Once the nozzle alignment is fixed to make the jets hit the spoons in the perfect spot, there should be a spot further along the rotation where water flings off still having some useful energy. Might be possible to capture some of that by turning that spray back at the spoons. Looks like doing this with a turgo design would be easier. Put a funnel beneath the wheel to catch the water that's deflected by the spoons. The funnel's top should be tilted in the rotation direction so the water coming down shoots straight down the funnel's throat. From the bottom of the funnel, a pipe narrowing down to a small opening curves around to aim somewhere at the spoons, down-spin from the upper nozzle. In other words catch the flow going through the wheel, make it do a U-turn, and accelerate it to hit the wheel a second time.
Have you considered abandoning the traditional turbine? and moving to a centrifugal pump, used as a generator? Actually sealing the water could lead to a significant improvement in efficiency.
You need some strategically placed louvers in the cylindrical turbine housing to allow water to escape out and not be recirculated and churned in the path of the pelton wheel. The louver principle is very much like a windage tray inside the reciprocating crankcase of a common internal combustion engine.
What about something that would let the exiting water escape and prevent it from splashing back completely. Something shaped like a roof mounted fan vent . The water would go between the blades and splash against outermost housing without being able to hit the spoons again
i think if you take the sleeve and perforate it with holes i think it would work great as the water would get caught by the perforations and drip down to the drain
I very much like the work you did with connections, concrete, etc, to make it easy to work on. These things need a lot of work at first when efficiency improvements are being done. I'd do a lot more experiments before committing to stainless. Get all the flow and bouncing issues/opportunities solved first. Whatever bouncing issue you have with the top, is likely happening on the bottom as well. You may want to increase the height of the box by a foot to prevent any bouncing from the bottom.
I would put some slots/louvers in the round wall. 1 or 2 just before the corner of the square frame should allow the excess water to get out and not stay in the main chamber rotating. That is only if the round wall increased efficiency.
Can I suggest some guide vanes on the inside edge of your housing, to very subtly direct the flow downwards. You could probably get away with them angled as little as 2 or 3 degrees downward
can you put the nozzle you use and where you bought them in the list if turbine components? thanks! this is really so interesting! will try build one!!!!
Looking into my dust collector the dust is by a fin or curved blade that. Diverts the dirt away from the walls . I’m sure you don’t need my advice , but there seems to be a similar situation.
You should lighten the turbine disc and make it have 3 spokes that have rounded edges to reduce the drag and the spinning momentum or make a air tight housing so you can suck all of the air out of a tube that runs out the top of the housing to take away most / all drag from the air then when you go to run the turbine you continue to suck in air out of the tube that prevents water from getting in through a multi cone system. It may sound confusing to some people but it makes sense to me.
I recommend removing the turbine housing walls complete and replacing them with 4 corner legs instead (and mounts to hold the nozzels). That way the water could exhaust out into the larger enclosure and drain without chance of splashback.
I think you need to keep the top of the dynamo dry through so water splashing around everywhere might not be so great.
Why not have the size of the housing another half as large to prevent splashback from being able to reach the pelton turbine wheel. If it still has the energy to do that, have vanes fitted to the inside of the housing - fitted at an angle to "capture" the exiting water - preventing the return of the cplashback. Think of internal baffles allowing the water to enter but not be able to reflect back. One could even have them angled to deflect the exiting water downwards as a means of preventing splashback
That was my thought too.
Exactly! Similar to a stator directing water onto a turbine propeller, but in reverse pushing spent energy water away from the spoons.
Exactly my thought to, turbine housing deflectors angled to channel wather outward or down or a bit more complicated out and down at the same time.
Yes I was just thinking the same. The turbine housing should be a bit larger and with the walls tilted downwads or even curved round an downwards like a house roof to bend the splashing downwards. I think actually a stainless steel baking bowl would do it. Though ruin the view we can see you filmed throig today in slow-mo. Thank you for your series. Learning a lot.
I agree bigger housing you can get 3/4 thick plexi would be superior to plywood resin/fiberglass too boat epoxy is very strong also he could turn side ways for horizontal different jet position too so that water is moving in one direction or dual stream focused in a reverse V so both streams are focused I dont see single side causing uneven bearing load because water is a solid and its fairly constant there is also the possibility of one jet followed by the other that way splash back is occurring later if you can imagine a clock and say the jet pushes it from 5 oclock the water leaves the spoons at about 12
Now, take your circular housing and make it a cone shape to direct the water down as it goes around :D
Then add a smaller turbine at the bottom of the spout to try and harvest some of that waste energy. And as water falls down the cone it should accelerate.
If you make this cone long enough, most of the centrifugal forces will be directed downwards by the acceleration of falling down. Jet the falling water onto a small very low weight turbine that is perpendicular so that the water wheel catches the water as it falls. I'm not sure what the speed of the water is in the turbine, but it seems pretty close to terminal velocity, so we probably wouldn't even have to be that big a cone. the biggest thing would be making sure the water flows freely from the spout without pooling up in the bottom of the cone. messing around with the angle of the cone can help with any turbulence.
@Eric Vercruyssen Because shape of the housing is not the isue here.
It looks to me that the turbine is spining too fast, he should use turbine with smaller diameter or conect it with generator able to get more power out of it at this RPMs.
This type of turbine have best performance when blades are moving with half of the speed of the water in the jet.
With half of the speed the water gonna hit the blade and transfer almost all of its kinetic energy into turbine blades.
Wrong direction of the jet can also be part of the problem.
Just thought of this. Great minds!
Or corkscrew rifle the rim to direct it down
Motor sounds like it’s struggling at first...
.....Pulls the 3 phase wires out of a puddle.
Motor speeds up and runs more efficiently....
“That was weird! It was acting like there was a short. I don’t know what thats was about...”
I kept on looking at those wires.... is he going to more them.... surely anytime now.... there in the water dude, move em.... nup.
Yes I wonder why he missed that!
Two ideas:
1. Can you reverse the direction of the round insert so the seam would catch the water and take it out of the housing?
2. Can you make a cone so that the water hits and goes down as soon as it hits?
Yeah the cone - I had in mind.
And a round enclosure with tight tolerances, but I don't think this type of spoons are made for that design, and will cause water drag when too tight.
Land to House cone was my thoughts too
@@jons6125 after looking at Langstons metal design he uses 4 sections of metal sloped down like a pyramid.
yep and maby make the housing veined
We are getting into turbo jet territory here lol. veins... guides.. I guess if you want to improve that is where it all comes down to.
Cone shape, so it splashes down
Cam to say this, he's thinking in too many 90deg angles.
That is an interesting idea.
I had the same idea. Doesn't even need to be a cone. Could be pyramid and still work a lot better than what he has. As long as it's moving more of the water down and out
Came here to suggest the same thing... or put some half inch by 4 inch slits long ways down the middle...
what about a spiral cone to channel the water down as well?
Given what I've seen in commercial turbines, your enclosure needs to be 2x that size and round, with the nozzles sticking out close to the wheels. Round should be good, but ideally it'd be slightly conical, so the water is directed down once it's flung off the turbine. You need enough distance for the water to miss the spoons as it reflects back off the wall.
At 9:12 it appears that the water circulating is hitting the jet, thus causing it to loose direction. Perhaps the permanent solution should indeed be a flattened down facing cone with little windows to let water escape just before the jets. Anyway, great job!
Would have thought a bigger box would help stop the splashback.
Also you should try and get some splash mud flaps. You'll see them on trucks (we do here in Australia), and look like the hook side of Velcro, except it's about 1/2 cm long.
They basically stop water splash back.
First thought that came to mind: A bigger box makes for extremely sloppy splash-back. 😂
LOVE THIS CHANNEL. The fact you are willing to try different ideas is what I love about this channel. I am a subscriber by the way. A simple solution you mentioned, to cut the turbulence is exhaust points for the excessive water at the corners. You have a vortex but excess water splashing back. Having a large hole on the corner would allow the water to spin, and then exit the main chamber. Keep up the great work,
Make the housing bigger....or why do you have the housing anyway? Use a splash guard.. the housing is "the pit"
This is the right idea for sure
The high speed is SO PRETTY! I love it! Watching the droplets move. Epic.
Thanks for testing taking the corners out. Had a feeling youd gain some efficiency. You could poke holes in the circular housing to let water through as it spins but not enough holes that it could come back. Let it drip down the corners essentially. The other thing you could do is make it thinner at the top than the bottom to encourage the water to go downwards.
you really should put those electrical connectors into a junction box.
no, the tingles make me feel good.
I was like im worried those lines in water
Joe Malovich lmaaaooooo
lmao🤣🤣🤣🤣
Username checks out
i would love to see how your setup up at the source is holding up. could you include an inspection in your next video?
3:30 very interesting to see that the reflected water jet changes direction as RPM increases. at low RPM it's directed almost backwards, then there's a point (i assume it's where turbine linear velocity reaches 1/2 of the jet velocity) the jet is dispersed sideways, and then it's just slightly redirected. it also means that at low RPM it transfers the most impulse from the beam to the wheel.
If the RPM is lower than a peripheral velocity of 1/2 of the jet velocity, there will be a higher torque on the shaft, but still a lower power output as some kinetic energy is returned to the water as it's thrown back. The point of best efficiency and power output is in fact when the peripheral velocity is 1/2 of the jet.
Of course, if he didn't match up the generator to the turbine, the point of highest total electrical power output might be different from the optimal rpm of the turbine due to the efficiency curve of the generator.
@@jonsen2k i wonder if instead of regulating nozzle flow by a valve, it might be better to regulate it by changing nozzle width. this way one could find the sweet spot for jet velocity when it's neither reflected forward nor backward on optimal generator rpm.
Idea: What if instead of a case housing you would use a frame just to hold and align everything but allow water to escape away from the spoons so it causes no windage?
Sounds good. I would also like to see that. A painted metal frame to hold the jets in place would let the water splash away further. The turbine can rest/attach on top of the frame and can also let you remove the turbine separate from the jets. Metal plates can be mounted on each side to direct the splash away from the turbine (out towards the corners).
Maybe it gets a bit messy, so the jets and piping could be covered with some splash protection instead.
The round enclosure does seem smoother, but the space is tighter. So a bit of give and take there I guess.
Really like your experiments :)
I thought this but then thought that the top of the generator would be getting splashed.
@@WhiskeyGulf71 Yes, but you can still have the acrylic plate connected to the turbine, so should be the same.
Adding a metal edge would make it stronger, and then it can rest on the bottom frame. Could also add a shroud around the top center to prevent water from getting there. Noticed some rust on one of the valves, but the rest seems to be more corrosion and splash resistant. Would be interesting to see how the shaft and bearings are doing now..
May be 3 points of contact in horizontal position. Might be less friction if it was vertical. And if it was not using bearings, but tight fit and oil.
(A metal alloy sleeve used as sacrificial material). Bearings definitely dont like water, and are less durable. So you have a really good point keeping water out of there :)
I'll have to re-watch how the turbine was put together now :)
So the motor is on top of the acrylic, and should not get splashed much. Would need to either extend the acrylic or make walls on the top side if the cage is to be skipped.
The bolt in the bottom is fixed, so no friction there. But then it's hanging on the top instead. But not much weight, so might not matter a lot which way it is installed. Probably simpler to just replace bearings now and then. :)
Just make the acrylic the size of the pit. The pit is the housing, and sit the acrylic and stator on the frame.
Maybe you could build a naked frame around the spoon side of turbine, and keep the perspex shield to protect the alternator section.
Bit like a four leg table design ,and incorporate a upright to strap wiring to away from water.
Also weld some sheet plate ,just in areas where jets come in. Then this way less water is splashing back onto spoons ??
This really got the comment section excited. Nice work on the investigation front
I can hardly keep up
Great video. I hope you are paying really close attention to the transition from your reinforced hosing thru your ball valve and thru your jet. You are effectively accelerating your water and any losses there will be easily quantified. You don't want to be having turbulence from square edges steep tapers etc. Just think what a water monitor looks like. I also suspect that this would work better in a horizontal axis. In this axis the water from the upper set of "cups" must drop thru the lower set of cups. You want the water hitting the cups, expending its kinetic energy to the cups and then getting a straight shot out of the way. You could simply use two parallel jets mounted to achieve the desired impact. It may also be desirable to put the ball valves some distance upstream from the nozzles to minimise their affect on your nozzles. An effective way of stopping water getting to an alternator without huge friction losses is to put a disc on either side of "barrier. The water can not pass the spinning discs because it is simply thrown off. Kind of like a continuous labyrinth seal. No physical contact to anything, just a tiny bit of windage.
Really nice to have that kind of things. How to build or to generate just to produce an electricity.
i wonder if holes in the round insert would help direct water away. Nice job so far excellent DIY project
*@Joe Malovich*
eg: 9:40 -ish. Maybe you can build a kind of protective cover for the jet-beam "upstream" inside the turbine, so the used water that goes around the edge doesn't cover the beam & both re-direct the beam & "steals" momentum from the beam.
Hey Joe! As many people said, a bigger housing diameter would prevent water from splashing back and hitting the jet.
From my experience in a company manufacturing small hydro (50-500 kW) turbines, vertical axis Peltons always have a big housing, let's take a 0.6 m wheel diameter, the housing would be around 2 m (3 times bigger!).
Anyway this is a very small turbine, so probably a housing diameter twice the wheel should be a good compromise.
One last "humble" opinion about the wheel: the amount of water combined with the head of your turbine would need bigger spoons. I say so because the jet seems to be quite big compared to the spoon size, which means the turbine is less efficient (water leaves the spoon with very high turbulence) and also more splashing all around.
I hope this may help.
Thanks for your videos and for sharing your experience.
As you said getting the water away from the alternator is key so with the round housing I would make some openings (semi circle cuts) along the top every few inches so the water can escape once it has hit the rotors and doesn’t splash back. also maybe adding some water deflectors before the nozzles on the round housing to send the water up or down so the “spent” water that has already hit the turbine fins doesn’t hit the new water coming in making the stream turbulent.
If you cut a hole in the liner where the water is splashing back at 4:31. The water would (hopefully) get trapped in the corner behind the liner and drop away
As many have commented already, I would like to see a total open design. This can be achieved with a fairly large metal frame and acrylic top. This will cause more water in your pit, yet it may solve many problems, I suspect that you could see 10% or more improvement. It should be pretty simple to do.
Perhaps make it taller so that less water is "sitting" on the turbine. That way it delivers it's energy then drop away as to not impose any drag loss.
Try a larger box with the ring around the pelton wheel formed as a cone with the larger end at the bottom. Like an inverted funnel.
You could try a perforated liner to allow the water to escape.
I agree with this guy. perforated inner circular liner with holes about 5cm to 10mm in diameter
I was going to say the same thing, but thought I would read through what others had already said. Possibly angle the holes so they would help direct the splashing water out.
You want a 10 degree taper on the side walls. Also need to shield the jets.
I wonder if an inverted bowl enclosure might be useful? At the angle of the jet and spray off the spoons, the side of the bowl at that point would encourage the splashback, and really any water which is ejected from the turbine as it spins, to be forced downwards and away, out of the enclosure.
Interesting. Have you thought about perforating or slotting the circular baffle?, just enough barrier to prevent the splashing back but thick enough to slow the water down and reduce the splashes from the square edges. This is all about impedance matching - ideally, it should look like there is no enclosure at all. I don't know if any of what I'm saying will really help, but that's what I'd be tempted to try
Joe. Place a strip inside the cylinder spiraling downwards. When the water deflects, it will be channeled downward. I would start with one but 2 or more may work better,
i think just havving a big circular housing with more space for water to escape rather then a box, then it would even be easier to make out of stainless?
What about adding a few corkscrewed strips inside your round insert to direct the water downwards as soon as it hits the surface? You’d probably only need one strip per side, a long gradual decline so it doesn’t slow the water too much?
Ide say have your houseing as close to the blades as possible to maximise flow, turbines are tight in fit not smaller than the housing
You could try 'coning' the round housing, if you 'coned' it downwards that would also help to keep the water from soaking your bearings
Drill holes in axial alignment with the turbine spoons in the round liner. This would allow the water into the gap between the round and square housing segments and likely eliminate all splash-back...
Joe, do you want the design 'rules' or guides for the parameters for the housings on vertical and horizontal Pelton wheels? Should have them lying around from my thesis somewhere.
Might help you to sort something that works as best as it can.
Sure, you can email them to me, malovich@gmail.com
Even though I'm going turgo it will be an interesting read.
@@JoeMalovich Should be in your inbox.
For those that are interested, all of this is from Pelton Turbines, Zhang 2016 and checked with a fair few other sources.
The casing design is very different if the turbine is vertical or horizontal, the horizontal casing that Joe is using here should be completely open underneath the turbine while being close up to the buckets on the top. The gap between the buckets going up vertically should be 0.3 turbine diameter, extending out to 0.6 turbine diameter when the curve is in line with the plane of rotation. After that, it can drop vertically to the drain.
The circular casing Joe added prevent windage, but to be ideal, it needs to have a curve added so that it blends into the top of the housing, and then curves down to meet the runner, with a larger gap at the tip of the turbine buckets. Not an easy thing to make without casting something or getting more creative than the gains that this will likely offer.
@@JoeMalovichI undertand that Turgo might be a solution to the splashing but the disadvantage of turgo is that the force of the jet is not aligned with the rotation and therefore I would assume angular losses.
New to the channel. What is the underground access leading to at 6:35 into the video? Looks great.
if you give the water an exit in the corners where the reflex off of the blades that appears to be in the corners . use the corners as a drain.
Hi Joe love and warm regards from India, I feel you must make a involute just big to fit the pelton wheel, you can visualise it as a "C" that's like half cut square, going around the pelton wheel will reduce the drag form a more uniform water flow over the wheel, also I recommend to add 4 more nozzles so a total of six nozzles with a enclosed involute specially made that just fits pelton wheel, should surely increase its efficiency, lovely work and a great design, great effort in that biting cold Joe, God bless and keep the good work going.
I am amazed at this technology.
I think around housing that folds completely around the peloton wheel with minimal clearance (like 2-3 mm) would be the best solution. This way the air moves basically at the same speed as the turbine and will have very low turbulence.
To get the water out you create two whole at the top and the bottom behind the the jet nozzle, which match the spray back from the nozzle.
To avoid that water is falling back in the upper hole (by a different nozzle), you need some kind funnel leading outwards.
I would say if you tighten up the clearance of the round housing to the turbine it will help.
Wh6 not have a cone shaped umbrella spaced over the impeller for the water to pass under but the splash would deflect away
At 3:26 you have the electrical connections of the power wires in the water? Might be a shortcut after all.
there is actually an ideal gap between the spoons and your outer wall. look into fan ducting, it's the same idea. but you really only want like 0.25-0.5" of clearance with the spoons, and you should probably drop your headspace above the spoons to about the same. what's the id you need, because I may be able to help you out with some stainless tube that's the right size
Awesome videos man. I've always loved your channel since you where at your old house. The new house is even better and to me although it's not always providing water it's still a awesome property for hydro. My next house when i look for one will have to have some kind of spring or water higher in elevation so I can make one. I already have 1.1kw solar system I built.
Greetings from Chapel Hill NC 🤘.
I've been following you for some time now.
Apologies for not subscribing sooner.
You're working projects are fantastic.
Can you run more small nozzles to use up the full flow rate? Does that give a proportionately higher power output? Long nozzle tubes with venturi inlets from the larger pipe will exit in a laminar flow. A fixed stator will direct the discharge water away from the rotor.
just before you mentioned a possible short, I noticed that the connectors for the 3 wires appeared to be in the water. That would tend to cause a shirt
Quentin Clark has a point. I remember looking at MWh pelton wheel housings, of the ones I've seen the shaft was horizontal, the nozzle came in from the side at the lower side of the wheel. Loads of space for the water to deflect and down and out away from the wheel. Not really applicable here but with the circular housing looks like the right idea, but it looks like it needs to be alot larger for it to work to keep windage away from the wheel.
You must allow the newly implemented round tub to spin freely, this allows centrifugal force to force water to outside edge
Of all the suggestions I feel this might be the most technically complex to implement.
you need to take the insert and flare it out so it's wider on the bottom than it is on the top. that will keep water to the outside insert and direct it downward naturally
I wonder if you added "guides" to the circular edge to guide water down? sorta like what you see on the barrel of a gun...? to direct water right down as fast as possible
Have you considered corregated culvert pipe with the spiral aiming down. Might just catch the overspray and guide it down without the backwash.
The perforated type would be a good way to go. The type we use down here for French Drains. www.metalculvertpipe.com/img/perforated-metal-culvert-pipe1.jpg
gravelydon I haven’t seen that version before but it’s more like a washing machine tub on steroids!
Pelton wheels should operate in open space or, as said below, the splashback decreases efficiency hence extractable power.
Greg Warner That’s the most sensible thing I’ve heard. Aint gonna get any splashback if there aint no enclosure.
What if you make the water guard like the drum of a washing machine? Have it full of holes to let the water be forced out from the turbine and run down the back away from the spoons. There is two way of doing this the other is a little harder to explain but will work too.
You should do a slope for the water to go down (a conic shape)
Could you line the case with spikey door mat to catch the water in a way that should minimize windage.
You have a large concrete block enclosure, why not make your circular box much larger to allow the water to fall away from the turbine instead of splashing back. Leave nozzle positions in same place.
I'm building a turgo in a stainless housing in short order.
Looks like just about anything to get the 'spent' water away would be helpful, gap in the top, holes/slots/diverter vanes. Perhaps even a stainless steel blower wheel (I.e. what gets use in HVAC blowers) with the vanes in the right direction could be an off-the-shelf solution that could be modified to work for your final enclosure? Just something to catch the water, move it away from the wheel to get it into an outer portion of the enclosure where the water can drop down to the drain.
Try a volute casing. Works in centrifugal pumps so in theory should avoid splash back on the pelton wheel because of the increasing diameter.
If u can direct the level of water vertically you could focus it downward and stop it from disrupting the jets.
This looks like so much fun!
you can get Teflon carving boards at dollar general to replace the plywood...
Have you thought about adding louvers to the circumference of the circular housing acting as sort of a one way valve taking the water away? Similar to a windage tray controlling oil inside of a performance engine.
could add a few downward angled fins to the round wall, to induce a downward vortex
if you use a funnel shaped surround, it might bring the water downwards when hitting the wall..
Look into windage trays for engines. They have slots so the oil can escape easily into the pan and get out of the crank case. Something similar here would let the water escape from the wheel and help keep it from splashing back.
Wouldn't making the box longer, at the face the nozzle is shooting along, help to mitigate the splash? More of a rectangle rather than a square. I would also make the box taller, so there is more space between the turbine and the walls. It should allow the high speed water to lose some momentum.
Joe, I just recently discovered your videos and what you are doing I think is really cool. I'm sure you have researched this topic at length but I build racing engines and understand fluid flow. I wondered what larger more commercial water turbine designs looked like and I found this website with a 10KW turbine. I wonder if you incorporated a similar turbine housing design if your water flow turbulence would increase the efficiency. I think this design (on the website) incorporates a down draft turbine blade design but the fact that the housing is both cylindrical and cone shaped allowed for the water pressure to dissipate and fall away. I wonder since your Pelton wheel requires more of a direct side impact with water flow, if you created a half donut shaped upper housing for the water to reflect off of and help smooth the turbulence of the squarish corners between your plexiglass and the cylinder. I imagine if you want to keep the upper lid visible, you could use clear casting resin to make a semi transparent "half-donut". Here is the site I found, have a look.
www.micro-hydro-power.com/Micro-Hydro-Turbine-Power-Dual-Nozzle-XJ30-10DCTF4_6-Z.htm
Your comment is on point. I plan to solve this issue by using a turgo runner which has all of is flow in one direction.
First time watcher. I think this is really neat. I wonder if a bigger box would allow the water to divert and not cause drag.
I just had a thought -- maybe if you made the housing conical so that it gets larger as it goes down to deflect the water downward it would reduce splashback. Like how a bullet trap is angled down instead of flat to prevent backward ricochet.
What if there were guides in the circular liner to slowly direct the downward, a spiral that directs the excess water downward? Maybe you can direct the excess water so the water goes under the next jet.
thats a viable option.
You could buy some thick *plastic* cutting boards (a.k.a. butcher blocks) for housing material instead of stainless. I'm not sure how they compare based on price, but neither one would warp from moisture.
Think of it like a rain tire. Shed the water by using radial cuts that direct water outside the circular baffle.
I would direct the jet toward the spoon as usual and add a baffle just at the initial impact spot(direct the initial), then after do the radial openings that direct water away.
Hi Make a new enclosure using the same lid but with 4 new sides at steep angles like a pyramid or tank armour to angle the overspray down to the ground. You would need to make nozzle extensions though.
Another idea is to cut strategicly placed vents in your baffle, sort of like the vents in a windage tray in a crank case of a motor.
What about adding some curved/cupped fins that would catch the water and direct it down at an angle towards the drain?
whether a round or square housing- After the water hits the paddles divergence needs to take place. Find out where the water goes after the paddles, trap it and get it out of the housing eliminating its ability to slow forward movement of the wheel.
Maybe add some small vanes in the inside of the drum, angled 45° down?
As the vortex gets going, the vanes should help the water become forced down and out
Larger, round housing, walls angled so that water hitting them is directed down. Something I'd try is shaped pieces to turn water back in the rotation direction after it flings off the spoons. Once the nozzle alignment is fixed to make the jets hit the spoons in the perfect spot, there should be a spot further along the rotation where water flings off still having some useful energy. Might be possible to capture some of that by turning that spray back at the spoons. Looks like doing this with a turgo design would be easier. Put a funnel beneath the wheel to catch the water that's deflected by the spoons. The funnel's top should be tilted in the rotation direction so the water coming down shoots straight down the funnel's throat. From the bottom of the funnel, a pipe narrowing down to a small opening curves around to aim somewhere at the spoons, down-spin from the upper nozzle. In other words catch the flow going through the wheel, make it do a U-turn, and accelerate it to hit the wheel a second time.
3:15 watching the wires chill in the water
Have you considered abandoning the traditional turbine? and moving to a centrifugal pump, used as a generator? Actually sealing the water could lead to a significant improvement in efficiency.
1:21 I’m getting your turbine rotation speed to about 1800 rpm:s. Could that be correct, you think??
I think if you have something like a fan housing that would help direct the water down and out of the way.
You could try go with a turgo turbine design to help direct the water downwards.
Most have suggested as I was going to suggest. Cone shaped shroud.
You need some strategically placed louvers in the cylindrical turbine housing to allow water to escape out and not be recirculated and churned in the path of the pelton wheel. The louver principle is very much like a windage tray inside the reciprocating crankcase of a common internal combustion engine.
What about something that would let the exiting water escape and prevent it from splashing back completely. Something shaped like a roof mounted fan vent . The water would go between the blades and splash against outermost housing without being able to hit the spoons again
i think if you take the sleeve and perforate it with holes i think it would work great as the water would get caught by the perforations and drip down to the drain
You should try a toataly enclosed housing more like a pump, or cone shape the liner downwards to expel excess water
I very much like the work you did with connections, concrete, etc, to make it easy to work on. These things need a lot of work at first when efficiency improvements are being done.
I'd do a lot more experiments before committing to stainless. Get all the flow and bouncing issues/opportunities solved first.
Whatever bouncing issue you have with the top, is likely happening on the bottom as well. You may want to increase the height of the box by a foot to prevent any bouncing from the bottom.
Why don't you cut a load of holes in the liner, so the water can escape through the liner instead or circulating around the inside?
That's the same thing I was thinking like a cheese greater
I would put some slots/louvers in the round wall. 1 or 2 just before the corner of the square frame should allow the excess water to get out and not stay in the main chamber rotating. That is only if the round wall increased efficiency.
Can I suggest some guide vanes on the inside edge of your housing, to very subtly direct the flow downwards. You could probably get away with them angled as little as 2 or 3 degrees downward
can you put the nozzle you use and where you bought them in the list if turbine components? thanks! this is really so interesting! will try build one!!!!
links in the description
Looking into my dust collector the dust is by a fin or curved blade that. Diverts the dirt away from the walls . I’m sure you don’t need my advice , but there seems to be a similar situation.
You should lighten the turbine disc and make it have 3 spokes that have rounded edges to reduce the drag and the spinning momentum or make a air tight housing so you can suck all of the air out of a tube that runs out the top of the housing to take away most / all drag from the air then when you go to run the turbine you continue to suck in air out of the tube that prevents water from getting in through a multi cone system. It may sound confusing to some people but it makes sense to me.