I hope you enjoyed the interesting engineering behind Kaplan turbines. If you have benefitted something out of this video, please consider to support us on / sabins Regards Sabin Mathew
I hope you enjoyed the interesting engineering behind Kaplan turbines. If you have benefitted something out of this video, please consider to support us on www.patreon.com/Lesics Regards Sabin Mathew
You mentioned at 5:35 that increasing area of draft tube will increase pressure so that bubbles won't form. But won't the increase in volume further reduce pressure? Because if we decrease the area too much then we know the water pressure going through the pipe will be high
@@SwaroopKadaba When you increase the area, velocity decreases or kinetic energy decreases. According to energy conservation to keep the energy constant, the pressure energy has to increase.
You should focus more on the titles and thumbnails of your videos. Even if your video content is excellent, people may not click on it if the titles and thumbnails are not engaging.
@@SabinCivil I'd love to see a full video on cavitation. I think your excellent animations could clear up the confusion. I've experienced it with water and fuel tanker trucks, but never have fully understood the phenomenon. Love the videos. Thanks
Outstanding! Every time I saw a description of Kaplan turbines before, it would stop after saying they were meant for low head, high volume situations. I could never imagine it had variable guide vanes and rotating blades. This is really quality content!
I'm a robotics engineer and back in my fluid dynamics classes in college, I've computed the relative speed between a fluid and a propeller many times, but I've never noticed that the optimal relative speed between the two was equal to the angle of attack, which now seems so obvious! Either change the angle of attack to match the relative speed of the flow or change the relative speed of the flow to match the angle of attack. Thank you for your animations, they help clarify so many concepts 🙏
Amazing Video...I am in Hydro project business and can say that the quality of information you shared is spot on. This is basic but a good introduction to someone relatively new to Kaplan turbine. Great to see that info on Cavitation was also shared...just some additional information, there is a way to determine the behaviour of complete water conducting system through a process called Transient Analysis, which governs the design...
Great video, and very clear graphics. You explained how they regulate alternative current, but how do they align the phase of the alternative current with the phase of the electric grid?
The generators are also motors. If a generator is receiving extra power from its turbine, the generator tries to rotate slightly faster and thereby it tries to advance its phase with respect to the phase of the grid. In so doing, the grid demands more power from it and thereby increases the load on it, inhibiting it from any further advancement. When a generator is receiving reduced power from its turbine, the opposite happens. Thus, all the generators are kept in lock step, so to speak. When a generator is first being brought on-line, its speed first is adjusted under local control until its frequency and phase are matched to that of the grid. Then the switches are engaged to place it online. If the switches are engaged when the generator is out of phase with the line, bad things happen! (Excessive current and excessive torque trying to jerk it into alignment.)
People might not know that you have a patreon, you should start mentioning it at start of the video or in bottom corner of the video. You also need to work on your presentation and pacing And do more yt shorts explaining old videos which don't get much views nowadays.
He should add a patreon watermark throughout the whole video in all videos. Also but not that important changing the banner to add social media and support stuff
Please take it as my suggestion. Being a Engineer I can suggest please try to show correct direction of rotation of the turbine. Because it may lead to wrong information or wrong education. Video is very intuitive. Good job. Please bring more.
A good video but I have a nitpick. It is not an airfoil to produce lift, it is a HYDROFOIL. This is important because unlike air water is incompressible so the mathematics, and hence the profile, of an efficient hydrofoil is quite different from that for an airfoil.
Very good video. I am surprised that the water flows parallel to the axis of the turbine, this video clarified many things for me. Not that I do anything useful with that specifically, but it is very entertaining to know and you never know if by association the idea is useful for something else.
🎯 Key Takeaways for quick navigation: 00:00 💡 *As turbinas Kaplan são as maiores entre todas as turbinas hidráulicas.* 01:09 🔄 *As turbinas Kaplan são mais adequadas para situações de grande fluxo de água e alta queda.* 02:18 🔧 *As comportas-guia das turbinas Kaplan regulam o fluxo de água de acordo com a demanda de energia.* 03:13 ⚡ *As lâminas das turbinas Kaplan são rotacionadas para manter a velocidade constante do rotor, mantendo a frequência da eletricidade produzida constante.* 04:38 🌪️ *As lâminas das turbinas Kaplan são torcidas para manter o ângulo de ataque ótimo em relação à velocidade relativa da água.* Made with HARPA AI
I have always thought that Francis Turbines were the ones meant to be used in high-pressure applications. Engineering isn't always so straightforward. I remember being about 12 years old visiting a hydropower facility that had a nice set of 8 Kaplan turbines, and when visiting the generator room, it was really hard to envision that I was actually over that huge case embedded in the concrete of the dam. The noise of that water rushing was really overwhelming.
ok I got an answer under some other comment who asked basically the same question. By increasing the diameter you slow down the flow thus increasing the pressure. It's basically the opposite principle as the Venturi effect.
never thought the turbines were vertical to the water body used as source. but it also makes me curious why vertical? is it just for ease of flow due to gravity? or maybe it's due to high pressure flow?
I would say it has to do with the wear of the turning parts, on it side the bottom will wear down much faster, and this way it's easier to distribute the water around the whole turbine
I could be wrong but are there not two separate forces acting on the blades? Splitting the water flow would cause a low pressure area blow each blade as is discussed but also the water hitting the top of the blade would be forced to deviate from its straight path thus imparting an inertial force to the blade. The amount of force imparted to the blade would depend on the angle and the speed of the water, both of which are variable.
You should focus more on the titles and thumbnails of your videos. Even if your video content is excellent, people may not click on it if the titles and thumbnails are not engaging.
Why does increasing the size of the draft tube with an end flare reduce the cavitation effect? One would think that increasing the volume of the tube in a low pressure situation would future decrease the water pressure resulting in more cavitation. I guess, because it causes an increase in flow rate that results in a pressure increase to more than compensate for the increase in post turbine tube volume?
Thank you for both enlightening me and confirming how much of a smartarse I am. I hadn't thought about blades being aerofoils. I'm still uncertain what the blades look like in those special hydro plants which are used as instant suppliers of electricity when there's a surge in demand. You know, the ones that pump the water back up to a top reservoir at night when the cost of electricity is cheaper.
5:37 How can increasing the diameter of the pipe for an already low pressure stream increase the pressure? The velocity is low and increasing the area will reduce velocity even further, which then will reduce the pressure right?
No, Energy is conserved, thus the Bernoulli Principle is applicable here, Kinetic Energy + Pressure Energy+Gravitational Potential Energy = Constant. Thus as Kinetic energy drops, Potential energy is unchanged, then the pressure Energy must rise.
Would think if a lift force wasworking on the top surface of the blade, it would spin the other way (pulling the top of the blade in the direction it is facing. Isnt this just kinetic energy turned into rotational energy? Edit: I see what they mean - the lift force is at the bottom of the blade and not the top. Still not sure that this is that majority of the force that turns the turbine.
5:34 how could increasing area result into increasing pressure 🤔 increasing in surface area of water wouldn't result into more bubbles ? Or its that the increased area will allow air to flow in opposite direction of water to manage pressure Wouldn't it be dangerous 🤔🤔🤔🤔🤔 Aaaaaa can't understand
I am bit confused how angle of attach is optimum when it is along the blade but not perpendicular to the blade. Can't that perpendicular angle of attach produce more energy harvest
If the generator has to run at a specific RPM how can the power output increase if it cant spin faster? I get that the vanes increase the flow rate and the blades adjust to maintain rpm but how does that increase output?
My (limited) understanding is that as load increases, so does the resistance experienced by the generator, and thus the turbine. By having more water flowing over the blades and adjusting the angle of those blades, the extra lift can generate more power by pushing back harder on the generator, overcoming the resistance to maintain output frequency.
every diagram and animation shows governor blades stationed verticaly, butin reality what about the fact that there are facilities with no casing structure but a concrede spiral chamber (wtich does the same job) the turbine sits on/inside the floor, the intake and the governor blades are positioned inside a narowing shroud about 40 cm from the floor, and the governor blades are positioned not verticaly but at an angle about 30 degrees (it could be less i have never mesured them down there) betwen the cros section and ground simply imagine a 90 degre angle where the hipotenuse is the cros section of the governor blade, the bottom cathetus is the floor , and the side cathetus would be the shaft, is there a efficency benefit in my described system becuse the water does not have to make a 90 degree turn. or am i just misunderstanding something , because now that i understand that it is a flow floil thing and not the other way around that the blade must be perpendicular towards the flow. Anyway grate video. Ps My family owns a small plant and im an operator and mechanic (self taught mentored by my father)
