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hydropower Bernd Sat, 15 Mar 2025 14:12:59 GMT No. 25644526 [Kohl] [Report thread]
Kaplan_Turbine.jpg
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Pelton_Turbine_04.jpg
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Francis_Turbine_High_flow.jpg
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Which turbine intrigues you the most?
Total posts: 34, files: 9 (Drowned at Sat, 15 Mar 2025 18:00:37 GMT)
Bernd Sat, 15 Mar 2025 14:20:47 GMT No. 25644566 >>25644596
Francis. It's really a genius design. I'm pretty sure exact same engine could be repurposed to act like a giant turbo compressor if given power from the other end, because it uses am impeller.
Bernd Sat, 15 Mar 2025 14:25:42 GMT No. 25644596
>>25644566 That's right. Some pumped-storage power plants do this. The generator then also serves as the motor.
Bernd Sat, 15 Mar 2025 14:36:47 GMT No. 25644671 >>25644713
depends on the head of course,but the compactness of the pelton is appealing
Bernd Sat, 15 Mar 2025 14:44:12 GMT No. 25644713 >>25644771 >>25644804
>>25644671 Pelton is the best for high usable heights with low water flow.
Bernd Sat, 15 Mar 2025 14:49:35 GMT No. 25644738
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Bernd Sat, 15 Mar 2025 14:53:01 GMT No. 25644771 >>25644825
>>25644713 Is that why anemometers kind of look like one? >spent a while arguing with a LLM about it and it eventually finally said something coherent that instead of Pelton, it looks more like Savonius design.
Bernd Sat, 15 Mar 2025 14:58:18 GMT No. 25644804
>>25644713 There are many small pelton electrical plants in the Sierra Nevada mountains. They look like little more than a small building with a pipe running down from high up the mountain. A friend of mine used to be a photographer for an electrical utility company in California and she would sometimes go to these places to photograph the facilities.
Bernd Sat, 15 Mar 2025 15:01:08 GMT No. 25644825 >>25644872
>>25644771 Anemometers work according to a different (aerodynamic) principle. The Pelton works with the impulse or kinetic energy of the water jet. Even if it sounds strange or confusing, the Pelton turbine is a normal pressure turbine because the water jet is under normal pressure after leaving the nozzle, but the water is very, very fast.
Bernd Sat, 15 Mar 2025 15:07:25 GMT No. 25644872 >>25644937
>>25644825 Both use cups, both are sensitive to slow, low pressure current, simple as.
Bernd Sat, 15 Mar 2025 15:16:31 GMT No. 25644937 >>25645374
>>25644872 >Both use cups Yes, but the water jet has a speed of approximately 100 m/s (at a useful height of approximately 500 m), and the orbital speed of the "cup" must be half that. It's different with an anemometer.
Bernd Sat, 15 Mar 2025 15:24:45 GMT No. 25645000 >>25645002 >>25645077
No love for wind power?
Bernd Sat, 15 Mar 2025 15:25:05 GMT No. 25645002
>>25645000 wind is just an impotent fluid
Bernd Sat, 15 Mar 2025 15:32:35 GMT No. 25645077 >>25645106 >>25645668
windenergie_400b.jpg
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>>25645000 Pumped-storage power plants are necessary for wind power. Wind blows when it wants to, not when the power is needed, so storage is necessary. Otherwise, wind power plants aren't bad in the right place. P (wind in Watt) = 1/2 * 16/27 * Rho (Luft 5/4 kg/m³) * A (Rotor m²) * v³ (m/s) * eta
Bernd Sat, 15 Mar 2025 15:35:08 GMT No. 25645106 >>25645161
>>25645077 they still suck but notice no one is reasonable enough to use them as you suggest I wish I had one for my well though
Bernd Sat, 15 Mar 2025 15:40:59 GMT No. 25645161
western-windmill.jpg
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>>25645106 Wind turbines were originally used only to pump water (Western mill), where the water reservoir is the storage, e.g. in the time of steam locomotives in the US. (Or for drainage in Holland.)
Bernd Sat, 15 Mar 2025 16:06:04 GMT No. 25645374 >>25645507
>>25644937 I see, that's a lot more optimized for energy generation, but aerodynamics are subset of fluid dynamics, there's no meaningful difference between the two beyond few variables like viscosity.
Bernd Sat, 15 Mar 2025 16:10:56 GMT No. 25645409 >>25645460
I like the elegance of the Francis turbine. Pelton has fun splishy-splashy, but that wastes energy (unless the rotational speed is exactly right). The high speed water jets also erode the little cups.
Bernd Sat, 15 Mar 2025 16:18:19 GMT No. 25645460
>>25645409 >unless the rotational speed is exactly right Das macht man auch. Eine Peltonturbine ist für 65 Jahre konzipiert, hält aber gut 100 Jahre.
Bernd Sat, 15 Mar 2025 16:24:39 GMT No. 25645507 >>25645511
>>25645374 > like viscosity. Viscosity, incompressible, steady-state, laminar, and most importantly, density** (kg/m³) Air = approx. 4/5 kg/m³ Water = 1000 kg/m³ (E kin = 1/2 * m * v²) **(volumetric mass density or specific mass)
Bernd Sat, 15 Mar 2025 16:25:42 GMT No. 25645511 >>25645550
>>25645507 Yes, and? Air is a fluid with different properties.
Bernd Sat, 15 Mar 2025 16:34:38 GMT No. 25645550
IMG_2334.JPG
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>>25645511 I have nothing against wind turbines; I even wrote my thesis on them, but I'm primarily interested in hydropower, especially small-scale power plants (up to 500 kVA [kW]). It's technically easier to generate electricity with hydropower.
Bernd Sat, 15 Mar 2025 16:46:30 GMT No. 25645656 >>25645766
>>25644526 >Which turbine intrigues you the most? number #2 Because I know how to build one.
Bernd Sat, 15 Mar 2025 16:47:36 GMT No. 25645668 >>25645730
>>25645077 why only 3 blades? surely you catch more air with more
Bernd Sat, 15 Mar 2025 16:54:22 GMT No. 25645730 >>25645802
>>25645668 Fast-rotating turbines have three rotor blades, while slow-rotating turbines have more. If you were to build a particularly large wind turbine (rotor diameter greater than 250 m), you would need more than three rotor blades, because with three rotor blades, the rotor tips would approach the speed of sound too close. But the number of rotor blades has nothing to do with energy transfer. The entire circular area is always taken into account.
Bernd Sat, 15 Mar 2025 16:59:17 GMT No. 25645766
Pelton.jpg
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>>25645656 also very large ones
Bernd Sat, 15 Mar 2025 17:02:30 GMT No. 25645802 >>25645857
>>25645730 The entire circular area wouldn't matter if the air is just rushing pass empty space?
Bernd Sat, 15 Mar 2025 17:09:16 GMT No. 25645857 >>25645866
1-Flügler-Wind_turbine.jpg
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>>25645802 When the rotor rotates, no air flows unused between the rotor blades, no matter how many or few blades there are.
Bernd Sat, 15 Mar 2025 17:10:59 GMT No. 25645866 >>25645925
>>25645857 This is unintuitive and I don't believe you
Bernd Sat, 15 Mar 2025 17:17:18 GMT No. 25645925 >>25645934 >>25645950
Bernoulli.png
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Bernoulli97.jpg
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>>25645866 There are many physical phenomena that are hard to believe.
Bernd Sat, 15 Mar 2025 17:18:26 GMT No. 25645934 >>25645968
>>25645925 That's not hard to believe t. didn't do physics after 10th grade in highschool
Bernd Sat, 15 Mar 2025 17:19:53 GMT No. 25645950
>>25645925 Makes sense to me t. simulates the fluid particles in my head
Bernd Sat, 15 Mar 2025 17:21:57 GMT No. 25645968 >>25645989
>>25645934 I know many people do not understand this example. Do you know the experiment where a capacitor charged with 10 kV suddenly has 20 kV when the plate distance increases? Many people don't understand that either.
Bernd Sat, 15 Mar 2025 17:24:11 GMT No. 25645989
>>25645968 It's obvious that water pressure decreases. It's also obvious that storm clouds paired with usually wet ground and humid air are very huge capacitors and their voltages are incomprehensible.
Bernd Sat, 15 Mar 2025 17:37:18 GMT No. 25646064
IMG_20190923_101428.jpg
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A synchronous generator coupled with a Kaplan turbine. (75 years old and still working perfectly)
Thread interest score: 4.7 Thread size: 144.83 kB