Well... not everyone is happy that I mentioned lift as an application of Bernoulli's equation! Here's my video on lift where I explore this in more detail: ua-cam.com/video/E3i_XHlVCeU/v-deo.html. ✈️✈️✈️ The Curiosity Stream and Nebula bundle is no longer available, but you can still sign up for Nebula and get acess to my bonus videos - use this link for 40% off! go.nebula.tv/the-efficient-engineer.
Sorry, but your explanation of what generates lift is completely incorrect. If it was correct, planes wouldn't be able to fly upside down, but they do it effortlessly. Sticking your hand out of the window of a moving car gives you a very good idea of what generates lift. You don't need airfoil shape for this. Also, check out this MIT lecture: ua-cam.com/video/edLnZgF9mUg/v-deo.html They got it right. Lift is impossible without angle of attack. Negative angle of attack creates negative lift.
@@vdubs1112 Why do you think that lift, as it is understood in aerodynamics, is necessary to make things fly? Lift is required for conventional planes to be able to climb. When a plane is not climbing it just glides. Lift is not required for gliding. What makes an arrow or a missile fly? No angle of attack, no airfoil... Using Bernoulli equation as an explanation of what generates lift is factually wrong because some planes don't have airfoil profile, and planes can fly upside down. This is a fact and Bernoulli did nothing to explain it. ua-cam.com/video/RML70yTD940/v-deo.html
@@vdubs1112 You are comfortably ignoring my questions. Are they too puzzling? Instead you resort to personal attacks. How sad, yet so common and so predictable. So much for an aerospace engineer. Can you give me examples of lift generated at zero angle of attack? Can you give me examples of planes climbing at zero angle of attack?
@@vdubs1112 I actually agree, that cambered airfoil dose generate some lift, but this is not why planes fly. Planes can fly without cambered airfoil, but they can't fly without utilizing and controlling angle of attack. Saying that planes fly due to utilization of Bernoulli principle is fundamentally wrong. Angle of attack creates an incomparably greater pressure difference and it is this pressure which does all the heavy lifting.
@@vdubs1112 the video says that this is how planes generate lift without even mentioning the pressure difference created by angle of attack. This is fundamentally wrong and misleading. Lift can easily be generated without cambered airfoil and planes can fly without it, but they won't be able to fly without utilizing angle of attack. Bernoulli principle does assist lift generated by angle of attack, but it is only a small portion of it.
@@el_chico1313 I’m a first year engineering student. About halfway into the semester. And I would say ‘hard’ is relative. If you apply yourself and commit to learning the processes and understanding them they will be ‘easy’ to you. This being said. The calculus is clicking with me and physics makes sense but the physics is a lot more difficult in my opinion when you have to rearrange equations algebraically to find the answer you need. If you go into engineering. Make sure you are good at algebra. Bc to understand calculus and to do the processes it requires you need to know the algebra behind what you do. As well as physics. For example our chapter this week are vectors of kinematic in 2 dimensions. We have a position function, velocity, and acceleration. And many times many. Many times you are required to rewrite the equation’s algebraically to find the variable you need. This is required for every problem. And that is more difficult to me than the math is. Because the math of calculus or whatever is pretty straightforward you solve it. Solve the limit. Find the derivative. Whereas physics it’s basically up to you and your intuition to find what you need in order to figure out problems like a projectiles velocity when it hits the ground.
With online classes, it was so hard to understand this. I've checked textbooks, websites, and countless videos, this is the best video that explains this.
I have been waiting for so long for yet another video on FM by you and I am glad it's finally here. I have a confession to make, I was legit scared of strength of materials until I came across your channel. You made me fall in love with the subject and I cannot thank you enough.
I think the one who made this simulation is a genius and master of what he or she was doing. Sometimes even a professor at the university could not explain things as easily as the one in this video. Greatly appreciate it.
These days I can hardly go anywhere without my GPS. In the early 2000s, I engaged my mind more to learn certain things, landmarks, and stuff essentially pay attention. These days I feel we are becoming mentally lazy. We instead need to think about the next vial video that adds no value to humanity except entertainment. Majority of the thinking is left to a few.
Great job buddy! I learned this almost over 10 years ago in my applied fluid mechanics class and this is a great reminder of that class! Fluid mechanics is really interesting topic and used in so many aspects of everyday life.
Unless you have a high understanding of mathematics(if u do great) it will be very hard to understand, if u are an engineering student there are probably fluid mechanics tutorials to solve navier stokes using various assumptions
That would be impressive, though unfortunately comprehending Navier-Stokes requires a high understanding of math, and results in the vast majority of flow being boiled down to non-linear solutions, which ultimately just mean that CFD is the only good option for simulating flow patterns. Though I would love to see a company like this try and explain NS, cause it is certainly one that would be good to have explained easier.
Fluids in motion and preassure is the only topic ive nailed down in this years physics lmao, litteraly my ticket to uni.so fun to do more research upon too
where was this video 4 years ago when we had no lecturer to teach us this ! great video thank you for explaining why it works rather than just "because it does"
Disappointed that this channel was just recommended to me today! I am very fascinated in engineering and upon seeing the visuals and explanations, you got yourself a new subscriber! Keep up the good work!
I went to engineering school in the early 70's and Thermo/mechanical engineering was my major. When I saw Bernoulli, I had to click on this video. I am sure others join me with reverence of the great men that discovered equations that emulate the physical world we live in. Level of genius involved to be the creator of the math involved...math is discovered and not invented...is hard to fathom really. Thank you and shout out to fellow ME's watching this and hope life has treated you kind. Tp me, people are born to be engineers. We don't really choose it, it chooses us.
I can't wait for the Navier-Stokes video! I found this channel yesterday and I've already watched all the videos :P Great content, man, it's gotta be the best animations/explanations I've ever seen on these topics.
@@geckokun2805 nope.... That was the best part of my life....I built "BAJA SAE" every year since my second year, I was in FSEA SUPRA and Hybrid cars for 1 year and SAE GOKART,EFFICYCYCLE and SOLAR vehicles on my 3rd year...I just have 1 regret though I have never been to an international event but I roamed all over my country just in 3 years and It was completed sponsored.. Now I just miss those days
Learnt, unlearnt and now relearnt after more than a decade. I still vividly remember the experiments we used to showcase on bernoulli's principle at sciene fairs at high school. Also vividly remember the venturi and orifice meter experiments at fluid mechanics laboratory in university. Equations like bernoulli's are simple yet powerful. Thanks for sharing 🙏
Thank you so much, not just for this video but for everything. The work ,the effort that you place to teach us is priceless. I know my appreciation and thanks will not pay you back your effort. But thank you from the bottom of my heart. I was struggling in different areas. And your videos made sense on how and why we use Math and Physics. My sincere appreciation
I am currently an Instrumentation Engineering student and I can definitely say this video covers everything that you need to know connected with the Bernoulli's equation and flow measurement using this equation. It is explained in the most appropriate and easy way including all the maths, for everyone to understand. Thank You for uploading. Subscribed.
I seriously LOVE your videos! They have helped me understand and make daunting concepts relatively simple to understand! Maybe do one on slipping/tipping?
The video was well done mate! My engineering boards are coming in a few months from getting postponed due to the pandemic and I'm grateful for the refresher.
back when I was in college over 13 years ago, I often went on youtube to try and find videos on the subjects I was having a hard time with, I don't know how long this channel has been going on for, but I wish I had found this particular video when I was taking my fluids mechanics classes! I graduated Chemical Engineering so this is a very important topic in my field.
This video is easy to understand because of the visual aids and most importantly, stunning to look at too! Thank you so much to all that involved in making this video!
This principal was fundamental in the development of the steam injector used for forcing cold water into a fully pressurized steam boiler for steam locomotives and other steam engines. The steam injector was a brilliant piece of engineering.
at 5:28 there is a picture of a wing showing where the "low-pressure" is above the wing, but I believe it's backwards. The low-preassure should be the greatest above the BACK of the wing where it thins out, not at the front.
3:30 the continuity equation holds regardless of whether you assume an incompressible flow or not. The assumption would help you get rid of the density change between 1 and 2.
Really well done video. A few comments: - the main assumption in all forms of the Bernoulli equation shown in this video is "inviscid flow", ie., neglect all viscous (fluid friction) losses. - in the derivation of the Bernoulli equation you do not have to assume the flow do be laminar. Actually, viscous losses are comparatively higher in laminar flow (= lower Reynolds number), so applying the Bernoulli equation to laminar pipe flow would give significant errors after a short distance. - agree with what TraneFine is saying below... - when you apply Bernoulli to pipe flow, or a contraction (Venturi meter, etc), you are really expanding the "streamline" derivation to a "streamtube" concept, ie., you are saying that the velocity is uniform at any given cross-section -- also known as 1-D flow.
Love the simplicity and clarity of this explanation! 👍🏼 I watched it as a refresher for my job. It actually makes me want to whip out the old Fluids book! 😂
Omg I have studied these things in my second of my college. I just mug it up all those things. But I searched a lot about fluid and solid mechanics alot in UA-cam. Can't find videos like this. Once I found this channel on while You uploaded the second video. I got clear idea about those thing you explained. Thank you for your quality videos. Please continue of posting videos. ❤️❤️❤️❤️❤️❤️
This is a top notch video. Actually made me want to get nebula. But the equations were well written and explained. The visuals were clear and intuitive.
Man, I can’t even explain the value in these videos. But I can approximate it to the value of attending a University to study engineering, except your videos are far better! Thank you, thank you, thank you
I've recently started watching your channel and I must say your videos are on next level. I've confusion in static, dynamic, hydrostatic and stagnation pressure. Can you please make a video on that as well?
This is what my teacher did as well. He just copied the derivation of the equation from the book to the whiteboard and didn't really explain anything.I doubt he understood anything about it himself.
I've loved your solid mechanics videos and recently I've seen the videos which are familiar with fluid mechanics. Great job and thank you! Expecting more phenomena like this.
@ 5:13 Wind tunnel tests reveal that fluid flowing over an airfoil *does not* travel faster than fluid flowing under it, therefore Bernoulli's principle cannot be used to explain how lift is generated. As a matter of fact, in wind tunnel tests the air above the airfoil is slowed down by the airfoil and actually reaches the trailing edge of the airfoil after the air that went below the airfoil. It is, of course, nonsensical if you think about it from the point of view of the air. We can assume that it's static before the arrival of the airfoil, and it's the airfoil that moves horizontally, not the air. The airfoil cuts through the air horizontally, forcing most air near the airfoil downward below the airfoil and a much smaller amount initially upward to make room for the airfoil as it pushes through the air. The majority of the air being forced downward creates an equal and opposite force on the wing that results in holding the plane aloft against the force of gravity. Contrary to the image in the video, the leading edge of the airfoil is an area of high pressure, not low pressure, as the leading edge pushes against the air, causing the air nearest the leading edge to move horizontally with the airfoil and thus to bunch up. This dynamically generated high pressure at the leading edge causes drag on the airfoil, the well-known bane of airfoil designers. The area of low pressure occurs further back along the airfoil where it tapers downward, dynamically creating an area with no air (vacuum) immediately above it that causes air above the airfoil to be sucked downward and follow the curve of the airfoil down. An airplane may stall if the angle of attack is too great, causing air to fill the vacuum from behind and below the airfoil instead of above it. Note that the airfoil's horizontal movement results in net downward movement of air both above and below the airfoil (at the trailing edge) and there is no actual horizontal movement of the air opposite that of the airfoil. Instead, some drag inducing air is actually displaced in the direction of the airfoil movement. If we insist on using Bernoulli's principle to understand airfoil design, we must understand that the dynamically generated high pressure at the leading edge of the airfoil induces downward, and also some upward and leftward velocity on the air as the airfoil pushes from the right and blocks rightward air movement out of the high pressure zone. The weight of the plane also adds to the dynamic pressure under the wing and increases downward air velocity, but it's that air pressure that holds the plane aloft. At the upper rear of the airfoil, the dynamically generated low pressure (vacuum) induces downward and possibly rightward and upward velocity to the nearby air of relatively higher atmospheric pressure so that pressure is quickly equalized in the wake of the airfoil.
Please provide a link to this test data which shows that fluid flowing over a lift-generating airfoil does not travel faster than fluid flowing below it. I don't believe it exists.
@@TheEfficientEngineer ua-cam.com/video/UqBmdZ-BNig/v-deo.html Your assumption was wrong, but my memory was also wrong. We both need to revise our theories. www.amasci.com/wing/airfoil.html
My revision: Wind tunnel tests do reveal that fluid flowing over an airfoil does travel faster than fluid flowing under it, but Bernoulli's principle is usually used erroneously when explaining how lift is generated (the longer path theory). As a matter of fact, in wind tunnel tests the air below the airfoil is easily seen to be slowed down significantly by the airfoil and actually reaches the trailing edge of the airfoil long after the air that went above the airfoil, despite having a shorter distance to travel past the typical airfoil shape. The air above the airfoil is not sped up the closer it is to the airfoil. On the contrary, the laminar flow very close to the airfoil is retarded by the airfoil, and the rest of the air over the airfoil arrives at the trailing edge virtually simultaneously. The longer path theory is, of course, nonsensical if you think about it from the point of view of the air. The air above the wing has no idea that it is supposed to meet up with the air under the wing, so it doesn't. Let's explore the real physics involved with a real airfoil on a real plane, not in a wind tunnel. We assume for simplicity that the air is static before the arrival of the airfoil, and it's the airfoil that moves horizontally (from right to left), not the air. As the airfoil cuts through the air horizontally, it forces some air near the airfoil downward below the airfoil and the rest of the air initially upward to make room for the airfoil as it pushes through the air. The weight of the plane on the air under the wing bunches the air up and forces it downward which creates an equal and opposite force on the wing that results in holding the plane aloft against the force of gravity. This dynamic air pressure under the wing retards the air flow beneath the wing, and then gets translated into downward air velocity. Contrary to the image in the video, the leading edge of the airfoil has to be an area of high dynamic pressure, not low pressure, as the leading edge pushes against the air, causing the laminar air nearest the leading edge to move horizontally with the airfoil and thus to bunch up. The dynamic pressure gets immediately translated into air velocity away from the high pressure area and the leading edge of the airfoil since the air is not confined to a vessel. The area of low pressure occurs not at the crest of the camber as depicted, but further back along the airfoil where the airfoil tapers downward, dynamically creating an area with no air (vacuum) immediately above it that causes air above the airfoil to be sucked downward and follow the curve of the airfoil down (review the Coanda effect). An airplane may stall if the angle of attack is too great, causing air to fill the vacuum from behind and below the airfoil instead of above it. Note that the airfoil's horizontal movement results in net downward movement of air both above and below the airfoil (at the trailing edge) and there is no actual horizontal movement of the air opposite that of the airfoil. Instead, some drag inducing air is actually displaced in the direction of the airfoil movement. If we insist on using Bernoulli's principle to understand airfoil design, we must understand that the dynamically generated high pressure at the leading edge of the airfoil induces downward, and also some upward and leftward velocity on the air as the airfoil pushes from the right and blocks rightward air movement out of the high pressure zone. The weight of the plane also adds to the dynamic pressure under the wing and increases downward air velocity, but it's that air pressure that holds the plane aloft. The dynamic pressure under the wing also displaces the air to the left relative to the air above the wing, retarding it in its traversal of the airfoil. At the upper rear of the airfoil, the dynamically generated low pressure (vacuum) induces downward and possibly rightward and upward velocity to the nearby air of relatively higher atmospheric pressure so that air pressure is quickly equalized in the wake of the airfoil.
I didn't refer to the "longer path theory"/"equal transit time theory" in the video. I just said that flow above the wing is faster than flow below it, without explaining why. The author of the page you linked to above states that there's nothing wrong with using Bernoulli's principle in the context of explaining lift. They refer to the circulation theory, which can be used to explain where the difference in velocity comes from, and so combined with Bernoulli's principle provides a more complete explanation of lift. I plan to cover this in more detail in an upcoming video.
I agree with you on every part in this video except the one at 5:09: whilst Bernoulli's theorem that high-velocity results in a decrease in pressure is, in fact, correct, it is not the reason how *lift* is on an airfoil, such as a wing on an *aeroplane* is created. This is due to *Newtons third law* _actio = reactio_ as the deflection of the air above the airfoil creates an opposite reaction. This reaction force allows the wing to create lift. I mean: imagine that it would, in fact, be Bernoulli's principle that was responsible for the creation of lift. What, if an aeroplane would fly upside down (like an aerobatic plane)? Or what about wings, that are symmetrically formed? Also: there is an old theory, that air velocity over an airfoil would increase to reach an air particle from under the wing at the end. This theory is also wrong and visualised in this video from Cambridge University: ua-cam.com/video/UqBmdZ-BNig/v-deo.html
@@leonardocortezgonzalez9043 Yes, the video oversimplifies it to the point of basically being wrong. But both effects need to be considered to fully explain how lift is generated.
I see that you both have already discussed the point of my comment. Yes, it is clear to me that Bernoulli’s theory is not wrong per se but just too oversimplified in the video to use it alone to describe the lift effect. It’s just that I have learnt in my physics course, that Newton’s third law would be more relevant for the creation of aerodynamic lift than Bernoulli. I guess it’s still a topic of discussion how much either principle is more or less relevant, as personally, I do in fact believe that it is actually Newton’s third law. This is because - as stated in my previous comment - how would lift be produced if an aeroplane flies with symmetric airfoils?. I really don’t know how that could be explained with sticking only to Bernoulli. And just as a disclaimer: I actually said that Bernoulli’s principle is not wrong in its actual meaning, but, yes, I guess I should have been a bit more precise that I meant that lift is not only a result of Bernoulli’s principle but also Newton’s third law rather than just focusing on Newton after that.
Actually it's just another way of describing what's going on. In physics there are often multiple approaches to understanding and analyzing a system. In the case of lift there is in fact an air velocity/pressure differential (and you are correct that the old hypothesis that this pressure differential came from particles "splitting and meeting" across an airfoil is entirely wrong) between the top and bottom of the wing and that pressure differential can generally account for the lift, or at least most of it. Newton's laws also apply of course, but instead of analyzing by pressure differential you would analyze by the mass and average downward velocity of the air coming off the airfoil. In the same vein you can analyze the system through conservation of energy. Now if you want a deeper understanding of what's specifically going with the air at and behind an airfoil, you have to have a more advanced understanding fluid dynamics including both turbulent and laminar flow. The way airfoils generate vortexes is particularly critical. As for flying upside down, that has to do with getting different results out of an airfoil with different angles of attack. Aerobatic planes in particular are generally made with symmetrical airfoil wings so that performance with negative angles of attack can more or less mirror positive angles. Some asymmetrical airfoils can still fly upside down but will perform very differently at negative angles than at positive angles and are therefore less predictable for the pilot when the plane is inverted.
I really enjoy and appreciate your videos. If you could do a video about tolerances-fits that would be amazing. Thank you and keep up the inspiring work.
Excellent illustration, very well explained. Recently came across this channel and saw a few videos about fluid mechanics as it is what I am studying rn and the grasp of ideas and concepts I had after watching these videos is just crystal clear. Thank you soo much :)
i don't think i intuitively understood bernoilli's principle, even after a college degree in engineering until this video. college is so worthless. good teaching/schooling/education is all about how well you're able to get a person to have that aha understanding, not how much money it gets, its brand name reputation, or how challenging they make their courses.
keep making great vids like centrifugal force , pascal law , continuity equation , venturi , orifice , water hammer , stall , detonation , surge , knocking , stagnation pressure , vibration , cavitation we all be really grateful if you did those
Very neat and clear explanation sir, but I just can't help but miss your videos on structural mechanics. Hope one day we will see some lectures on macro-mechanics of composite materials from you. Keep up the good work!
Hats off to you sir.! You are also a great personality to witness sir. Though you don't mention in your videos but I do get motivation and inspiration at the end of the video to try to follow your path.! Sir, can you please explain why for an airfoil you represented the low pressure with a much more area diagram than for pressure below airfoil, is it a free hand type of pressure diagram? Thank you sir for your videos & presence again.!🙏
I think Bernoulli's equations play a minor part in wing lift, and the main emphasis should be directed toward Newton's Third Law of Motion which says for every action there is an equal and opposite reaction. If a plane's wing is being pushed up, then the equal and opposite reaction is air being pushed down. Airplane wings are usually tilted upward in front by four degrees, which creates more force on the bottom of the wing than on the top surface, thereby creating a tremendous upward force on the bottom of the wing producing lift. I seriously doubt the additional small amount of distance the air requires to travel over the top of the wing surface creates a pressure differential large enough to produce the necessary lift.
I think u are not able to make the connection between these concepts... Actually it is interconnected... I.e. the shape of the wing and the tilt contributes to the low velocity... The key here is reducing the velocity below the wing which cause not just the drag and lift effect but also increase in pressure below the wing span... Which mean relatively higher velocity and lower pressure in the upper wing portion...
@@deepaksubba9527 - I perfectly understand the interconnectedness of the principles involved. I am just stating that Newton's law is the predominate issue here.
@@cwj9202 I agree about Newton's Third being important but the pressure differential can't be underestimated. The pressure differential is not just dictated by the thickness of the wing but by the difference in boundary flow conditions on the upper and lower portions. The flow is much more turbulent on the upper portion (the 4 degree tilt mentioned ensures this) resulting in a significant increase in velocity and corresponding decrease in fluid stagnation pressure on the upper portion relative to the lower
@@ilovekianna21111 --- I will not disagree with the physics you mention, but I think they are minor in comparison to the principles of Newton's third law of motion.
@@cwj9202 I dont understand why bernullis principle is always used to explain wing lift eventhough newtons ? law is so much easier to explain( and isnt countrrintuitive to many people as decreased pressure st higher speed is) also it doesnt explain lift from symmetrical airfoils
Great video and animations as usual. Thanks a lot. A questionn about the Pitot tube : Why do you assume that the flow doesn't enter in the tube ? In an other words, why do you assume that the stagnation point is at the entry of the tube, rather than at the end of it, where the stagnation pressure measurement takes place ?
I have a daily homework on this topic on Sunday. I did not understand this topic, but when I watched this video, I understood a little of it 😂👍 Because the language you speak is not my mother tongue. شكرا❤
I spotted a mistake. At 3:30 you say that the continuity equation is valid under hypothesis of incompressible fluid, which is wrong. The right hypothesis for the continuity should be the steady state condition. Nevertheless, excellent job! Keep up the good work!
3:37 I think there might be a mistake in the script. Mass flow rate stays constant regardless of compressibility. Nozzle calculations for compressible fluid ride on the fact that mass flow rate is constant regardless volumetric flow rate.
At the end of the lecture in which he introduced Bernoulli's equation, my Fluids professor said, "just remember, what goes in that end has to come out this end." Easy peasy.
Would you consider creating a video on your process in Blender for these videos? Or link some resources you used to develop your skills in this area? I am a young lecturer at a university and I want to build up my own catalog of content like this, I've shared your videos with my students and they love them!
Hi Jon, thank you for sharing the videos! There are many Blender tutorials on UA-cam which explain the software far better than I ever could, so I haven't planned on creating any such videos myself. I talk a bit about my specific workflow on my Patreon page (www.patreon.com/posts/36136936), but feel free to email me at hello@efficientengineer.com if you have questions or anything you would like to discuss.
being a neet aspirant its really difficult to understand concepts of physics this video i found randomly on clicking today and as my visual power is good i understood the whole of it in just 13:45 time. .keep it up @the efficient engineer😇😇☺
11:04 fun fact about those 3 assumptions is that all 3 of them are, technically, not true. They're 'usually close enough to being true so it doesn't significantly impact the outcome' but they are never, *EVER*, 100% true. And thus it's important to realize that Bernoulli's Equation is, at best, an 'estimation'. For a tool, that's perfectly fine.
We’re engineers, we only depend on real world application. So it not being 100% doesn’t really matter as there is a margin of error in every real world tool.
@@markjones6894 Very true. I just found it important to point out because in the video I didn't get the feeling this VERY IMPORTANT aspect of engineering was being properly covered... half of engineering is balancing the margins of accuracy of equations against the margins of accuracy of material properties against the margins of accuracy of operating conditions against the margins of intelligence of the intended users etc etc etc... It's all just a juggling act really. XD
@@jimsagubigula7337 That's incorrect. The law of conservation of energy is absolute, and that's just the first one I can think of off of the top of my head... the WAY in which energy is conserved might be difficult to measure as it can transform in different kinds but the law that all of it is conserved is absolute as far as I'm concerned.
Bruh watch video from 5:08 to 5:30. In this time span he explains how is the force created in the first place which is by the Bernoulli’s principal. Then you can apply 3rd law that the force (whose creation is exolained by bernoulli’s principle ) push air down which result in pushing wing up
Well... not everyone is happy that I mentioned lift as an application of Bernoulli's equation! Here's my video on lift where I explore this in more detail: ua-cam.com/video/E3i_XHlVCeU/v-deo.html. ✈️✈️✈️
The Curiosity Stream and Nebula bundle is no longer available, but you can still sign up for Nebula and get acess to my bonus videos - use this link for 40% off! go.nebula.tv/the-efficient-engineer.
Sorry, but your explanation of what generates lift is completely incorrect. If it was correct, planes wouldn't be able to fly upside down, but they do it effortlessly. Sticking your hand out of the window of a moving car gives you a very good idea of what generates lift. You don't need airfoil shape for this. Also, check out this MIT lecture: ua-cam.com/video/edLnZgF9mUg/v-deo.html They got it right. Lift is impossible without angle of attack. Negative angle of attack creates negative lift.
@@vdubs1112 Why do you think that lift, as it is understood in aerodynamics, is necessary to make things fly? Lift is required for conventional planes to be able to climb. When a plane is not climbing it just glides. Lift is not required for gliding. What makes an arrow or a missile fly? No angle of attack, no airfoil... Using Bernoulli equation as an explanation of what generates lift is factually wrong because some planes don't have airfoil profile, and planes can fly upside down. This is a fact and Bernoulli did nothing to explain it. ua-cam.com/video/RML70yTD940/v-deo.html
@@vdubs1112 You are comfortably ignoring my questions. Are they too puzzling? Instead you resort to personal attacks. How sad, yet so common and so predictable. So much for an aerospace engineer. Can you give me examples of lift generated at zero angle of attack? Can you give me examples of planes climbing at zero angle of attack?
@@vdubs1112 I actually agree, that cambered airfoil dose generate some lift, but this is not why planes fly. Planes can fly without cambered airfoil, but they can't fly without utilizing and controlling angle of attack. Saying that planes fly due to utilization of Bernoulli principle is fundamentally wrong. Angle of attack creates an incomparably greater pressure difference and it is this pressure which does all the heavy lifting.
@@vdubs1112 the video says that this is how planes generate lift without even mentioning the pressure difference created by angle of attack. This is fundamentally wrong and misleading. Lift can easily be generated without cambered airfoil and planes can fly without it, but they won't be able to fly without utilizing angle of attack. Bernoulli principle does assist lift generated by angle of attack, but it is only a small portion of it.
I am a Mechanical Engineer and I can say this is an excellent explanation.
Well done.
is the math and physics hard like is it intuitive or abstract? thinking about microtechnology studying
@@el_chico1313 I’m a first year engineering student. About halfway into the semester. And I would say ‘hard’ is relative. If you apply yourself and commit to learning the processes and understanding them they will be ‘easy’ to you. This being said. The calculus is clicking with me and physics makes sense but the physics is a lot more difficult in my opinion when you have to rearrange equations algebraically to find the answer you need. If you go into engineering. Make sure you are good at algebra. Bc to understand calculus and to do the processes it requires you need to know the algebra behind what you do. As well as physics. For example our chapter this week are vectors of kinematic in 2 dimensions. We have a position function, velocity, and acceleration. And many times many. Many times you are required to rewrite the equation’s algebraically to find the variable you need. This is required for every problem. And that is more difficult to me than the math is. Because the math of calculus or whatever is pretty straightforward you solve it. Solve the limit. Find the derivative. Whereas physics it’s basically up to you and your intuition to find what you need in order to figure out problems like a projectiles velocity when it hits the ground.
@@promfgamer3699 I agree, Curiosity in any type of knowledge will cure all the "hard" part over time
Where you're from..
I want to make a college project which should be unique...
So please help me in the making project
Lmao yess I honestly I ask so many question this explained everything
With online classes, it was so hard to understand this.
I've checked textbooks, websites, and countless videos, this is the best video that explains this.
ok, i'll give this video a shot.
@@G23_12 How was it?
@@asj2020 I didn’t pay attention, I was too busy playing tiny wings on my phone...derp.
Which grade are you being studying in man?
@@Hero_Alan College level haha
I have been waiting for so long for yet another video on FM by you and I am glad it's finally here.
I have a confession to make, I was legit scared of strength of materials until I came across your channel. You made me fall in love with the subject and I cannot thank you enough.
That's awesome, glad to hear it! :) Strength of materials is such an interesting topic!
Kudos for your emotional comment....
ua-cam.com/channels/gnO_q7xjxSYotvyUMgwzEA.htmlvideos
Aeroplane, hut terrace blow off in storm follows this principle p+ 1/2 pgh+ pv^2 = constant
its best
I think the one who made this simulation is a genius and master of what he or she was doing. Sometimes even a professor at the university could not explain things as easily as the one in this video. Greatly appreciate it.
How the f were people able to discover/invent these things in the 19th/20th century, while I can only understand it with 3d visuals.
What else were they able to do back then? Not like they had any video games, social media or anything like that to stimulate their minds.
It's humbling for sure
These days I can hardly go anywhere without my GPS. In the early 2000s, I engaged my mind more to learn certain things, landmarks, and stuff essentially pay attention. These days I feel we are becoming mentally lazy. We instead need to think about the next vial video that adds no value to humanity except entertainment. Majority of the thinking is left to a few.
@@omogaju i thought you meant u lived in the early 20's lol
Justice Cruz 😂 nice one
Bruh, just in time for my newly started fluid mechanics class, thanks!
Good luck
Nope, you're too earlier
Get that absolute raise of energy recovery my dude
what a good timing! i need this for my fluid dynamics exam on saturday :)
Great job buddy! I learned this almost over 10 years ago in my applied fluid mechanics class and this is a great reminder of that class! Fluid mechanics is really interesting topic and used in so many aspects of everyday life.
ua-cam.com/channels/gnO_q7xjxSYotvyUMgwzEA.htmlvideos
A video on Navier-Stokes and ways to solve this would be a perfect follow up to this.
Definitely!!
I’m afraid that it would be too hard to explain it in an understandable way.
Unless you have a high understanding of mathematics(if u do great) it will be very hard to understand, if u are an engineering student there are probably fluid mechanics tutorials to solve navier stokes using various assumptions
That would be impressive, though unfortunately comprehending Navier-Stokes requires a high understanding of math, and results in the vast majority of flow being boiled down to non-linear solutions, which ultimately just mean that CFD is the only good option for simulating flow patterns. Though I would love to see a company like this try and explain NS, cause it is certainly one that would be good to have explained easier.
hard to explain , hard to solve
Fluids in motion and preassure is the only topic ive nailed down in this years physics lmao, litteraly my ticket to uni.so fun to do more research upon too
where was this video 4 years ago when we had no lecturer to teach us this ! great video thank you for explaining why it works rather than just "because it does"
I've got an exam on this tomorrow! I knew following this channel would come in handy!
How did it go?
@@thelaurens1996 I'm James' second account. It went pretty well in the first half, but I failed the second part of the exam.
Learning is a raise In all rejected goals
Disappointed that this channel was just recommended to me today! I am very fascinated in engineering and upon seeing the visuals and explanations, you got yourself a new subscriber! Keep up the good work!
ua-cam.com/channels/gnO_q7xjxSYotvyUMgwzEA.htmlvideos
Bro...who taught you this god level of editing 😍😍
Bhai ye to create na kiya hai
🎉
OFCOURSE ,ALMIGHTY GOD, inspired him. because he worked so much.
@@ahmetbuyukumman3544 Kapp
@Mahmoud Abdlshafi sez u
I went to engineering school in the early 70's and Thermo/mechanical engineering was my major. When I saw Bernoulli, I had to click on this video.
I am sure others join me with reverence of the great men that discovered equations that emulate the physical world we live in. Level of genius involved to be the creator of the math involved...math is discovered and not invented...is hard to fathom really.
Thank you and shout out to fellow ME's watching this and hope life has treated you kind. Tp me, people are born to be engineers. We don't really choose it, it chooses us.
Sometimes I watch your videos just because they are so pleasant and beautiful to look at. I love your animations, and how minimalistic they are 😍👍👍
What an outstanding channel, the explanation and illustration on these videos is superb. I wish I had discovered it sooner!
One of the best educational video ever. Brief and easy to understand. Great job!
I can't wait for the Navier-Stokes video! I found this channel yesterday and I've already watched all the videos :P Great content, man, it's gotta be the best animations/explanations I've ever seen on these topics.
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Learning Bernoulli's was when I knew I wanted engineering to be my path.
that's awesome
Almost same to me....but I came through Planes and Now I'm a Mechanical Engineer
@@gouthamkumar1750 wow
@@gouthamkumar1750 was it hard?
@@geckokun2805 nope.... That was the best part of my life....I built "BAJA SAE" every year since my second year, I was in FSEA SUPRA and Hybrid cars for 1 year and SAE GOKART,EFFICYCYCLE and SOLAR vehicles on my 3rd year...I just have 1 regret though I have never been to an international event but I roamed all over my country just in 3 years and It was completed sponsored.. Now I just miss those days
I just had my fluid mechanics exam yesterday!!The Exam was pretty good but the reality is, I'm understanding the right concepts now.
Studied all of this at Jet School when I was in the Marine Corps! Lots of memories! Good instruction. 🙂
Learnt, unlearnt and now relearnt after more than a decade. I still vividly remember the experiments we used to showcase on bernoulli's principle at sciene fairs at high school. Also vividly remember the venturi and orifice meter experiments at fluid mechanics laboratory in university. Equations like bernoulli's are simple yet powerful. Thanks for sharing 🙏
ua-cam.com/channels/gnO_q7xjxSYotvyUMgwzEA.htmlvideos
Thank you so much, not just for this video but for everything. The work ,the effort that you place to teach us is priceless. I know my appreciation and thanks will not pay you back your effort. But thank you from the bottom of my heart. I was struggling in different areas. And your videos made sense on how and why we use Math and Physics.
My sincere appreciation
ua-cam.com/channels/gnO_q7xjxSYotvyUMgwzEA.htmlvideos
I study this on college when no online education existed Nice to remember this equation ❤️
good for you, i hardly remember F = ma
You learn this is college? Bro im learning this is highschool idk why these shtters keep putting high level stuff into kids syllabus. 11th grade btw
@@skullmax3595 I am late but actually in some Asian countries we say college to grade 11,12 and after that is university
I am currently an Instrumentation Engineering student and I can definitely say this video covers everything that you need to know connected with the Bernoulli's equation and flow measurement using this equation. It is explained in the most appropriate and easy way including all the maths, for everyone to understand. Thank You for uploading. Subscribed.
I am an environmental engineer and you have helped me with my courses such as fluid mechanics and water supply. thanks. 🙏
Why do you know I just learned Bernoulli's Equation and didn't quite understand it...
Thousands of thanks!
Its one of the best Engg formulaes
I was pondering on this topic, but the way he made it clear is just amazing.
A thumping *Thanks* from my side
Your videos are an inspiration, they spark a curiosity in me i had long thought to be lost.
I'll make sure to feed the flame, thank you.
I feel the same !!
dude's voice is a literal lullaby...i drifted off in the middle....jokes apart...brilliant representation and explaination..thanks buddy!!
I seriously LOVE your videos! They have helped me understand and make daunting concepts relatively simple to understand! Maybe do one on slipping/tipping?
I was trying to wrap my head around this and this video finaly made the concept click in my head, thank you!
The video was well done mate! My engineering boards are coming in a few months from getting postponed due to the pandemic and I'm grateful for the refresher.
ua-cam.com/channels/gnO_q7xjxSYotvyUMgwzEA.htmlvideos
back when I was in college over 13 years ago, I often went on youtube to try and find videos on the subjects I was having a hard time with, I don't know how long this channel has been going on for, but I wish I had found this particular video when I was taking my fluids mechanics classes! I graduated Chemical Engineering so this is a very important topic in my field.
after a weekend with my mechanical engineer friends I’ve watched this and understand the weekend easily as an electronics engineer :)
This video is easy to understand because of the visual aids and most importantly, stunning to look at too! Thank you so much to all that involved in making this video!
Having this in my fluid mechanics class, great explanation
This is probably the best video I have ever seen in this area. Well Done. Please continue in the area of Fluid Mechanics
This principal was fundamental in the development of the steam injector used for forcing cold water into a fully pressurized steam boiler for steam locomotives and other steam engines. The steam injector was a brilliant piece of engineering.
at 5:28 there is a picture of a wing showing where the "low-pressure" is above the wing, but I believe it's backwards. The low-preassure should be the greatest above the BACK of the wing where it thins out, not at the front.
3:30 the continuity equation holds regardless of whether you assume an incompressible flow or not. The assumption would help you get rid of the density change between 1 and 2.
I really appreciate how you broke down each part of the Bernoulli equation and provided practical examples*
Really well done video.
A few comments:
- the main assumption in all forms of the Bernoulli equation shown in this video is "inviscid flow", ie., neglect all viscous (fluid friction) losses.
- in the derivation of the Bernoulli equation you do not have to assume the flow do be laminar. Actually, viscous losses are comparatively higher in laminar flow (= lower Reynolds number), so applying the Bernoulli equation to laminar pipe flow would give significant errors after a short distance.
- agree with what TraneFine is saying below...
- when you apply Bernoulli to pipe flow, or a contraction (Venturi meter, etc), you are really expanding the "streamline" derivation to a "streamtube" concept, ie., you are saying that the velocity is uniform at any given cross-section -- also known as 1-D flow.
Love the simplicity and clarity of this explanation! 👍🏼
I watched it as a refresher for my job.
It actually makes me want to whip out the old Fluids book! 😂
so beautifully animated. I wish all concepts of Physics could be explained like this. Such a great channel.
I have to say that this is THE BEST video explaining Bernuli's equation principle !! well done and thanks you :)
Your videos are incredible and informative. Thank you a lot and please keep up the good work!
Omg I have studied these things in my second of my college. I just mug it up all those things. But I searched a lot about fluid and solid mechanics alot in UA-cam. Can't find videos like this. Once I found this channel on while You uploaded the second video. I got clear idea about those thing you explained. Thank you for your quality videos. Please continue of posting videos. ❤️❤️❤️❤️❤️❤️
this is the most legit video I have ever seen in my entire life.
This is the best explanation of Bernoulli equation ever. Thanks a ton 👍
This is a top notch video. Actually made me want to get nebula. But the equations were well written and explained. The visuals were clear and intuitive.
ua-cam.com/channels/gnO_q7xjxSYotvyUMgwzEA.htmlvideos
I watched 10 videos on this topic and this video cleared all my concepts...!!!
The confusing line of thought is not "more speed equals more pressure", it's "less volume equals more pressure".
Man, I can’t even explain the value in these videos. But I can approximate it to the value of attending a University to study engineering, except your videos are far better! Thank you, thank you, thank you
I've recently started watching your channel and I must say your videos are on next level.
I've confusion in static, dynamic, hydrostatic and stagnation pressure. Can you please make a video on that as well?
ua-cam.com/channels/gnO_q7xjxSYotvyUMgwzEA.htmlvideos
So refreshing to see this type of content. Thanks for helping me understand this in depth
our professor told us just the equation and explained nothing else, thanks for this video
This is what my teacher did as well. He just copied the derivation of the equation from the book to the whiteboard and didn't really explain anything.I doubt he understood anything about it himself.
I've loved your solid mechanics videos and recently I've seen the videos which are familiar with fluid mechanics. Great job and thank you! Expecting more phenomena like this.
@ 5:13 Wind tunnel tests reveal that fluid flowing over an airfoil *does not* travel faster than fluid flowing under it, therefore Bernoulli's principle cannot be used to explain how lift is generated. As a matter of fact, in wind tunnel tests the air above the airfoil is slowed down by the airfoil and actually reaches the trailing edge of the airfoil after the air that went below the airfoil.
It is, of course, nonsensical if you think about it from the point of view of the air. We can assume that it's static before the arrival of the airfoil, and it's the airfoil that moves horizontally, not the air. The airfoil cuts through the air horizontally, forcing most air near the airfoil downward below the airfoil and a much smaller amount initially upward to make room for the airfoil as it pushes through the air. The majority of the air being forced downward creates an equal and opposite force on the wing that results in holding the plane aloft against the force of gravity. Contrary to the image in the video, the leading edge of the airfoil is an area of high pressure, not low pressure, as the leading edge pushes against the air, causing the air nearest the leading edge to move horizontally with the airfoil and thus to bunch up. This dynamically generated high pressure at the leading edge causes drag on the airfoil, the well-known bane of airfoil designers. The area of low pressure occurs further back along the airfoil where it tapers downward, dynamically creating an area with no air (vacuum) immediately above it that causes air above the airfoil to be sucked downward and follow the curve of the airfoil down. An airplane may stall if the angle of attack is too great, causing air to fill the vacuum from behind and below the airfoil instead of above it.
Note that the airfoil's horizontal movement results in net downward movement of air both above and below the airfoil (at the trailing edge) and there is no actual horizontal movement of the air opposite that of the airfoil. Instead, some drag inducing air is actually displaced in the direction of the airfoil movement.
If we insist on using Bernoulli's principle to understand airfoil design, we must understand that the dynamically generated high pressure at the leading edge of the airfoil induces downward, and also some upward and leftward velocity on the air as the airfoil pushes from the right and blocks rightward air movement out of the high pressure zone. The weight of the plane also adds to the dynamic pressure under the wing and increases downward air velocity, but it's that air pressure that holds the plane aloft. At the upper rear of the airfoil, the dynamically generated low pressure (vacuum) induces downward and possibly rightward and upward velocity to the nearby air of relatively higher atmospheric pressure so that pressure is quickly equalized in the wake of the airfoil.
Please provide a link to this test data which shows that fluid flowing over a lift-generating airfoil does not travel faster than fluid flowing below it. I don't believe it exists.
@@TheEfficientEngineer ua-cam.com/video/UqBmdZ-BNig/v-deo.html Your assumption was wrong, but my memory was also wrong. We both need to revise our theories. www.amasci.com/wing/airfoil.html
My revision:
Wind tunnel tests do reveal that fluid flowing over an airfoil does travel faster than fluid flowing under it, but Bernoulli's principle is usually used erroneously when explaining how lift is generated (the longer path theory). As a matter of fact, in wind tunnel tests the air below the airfoil is easily seen to be slowed down significantly by the airfoil and actually reaches the trailing edge of the airfoil long after the air that went above the airfoil, despite having a shorter distance to travel past the typical airfoil shape. The air above the airfoil is not sped up the closer it is to the airfoil. On the contrary, the laminar flow very close to the airfoil is retarded by the airfoil, and the rest of the air over the airfoil arrives at the trailing edge virtually simultaneously.
The longer path theory is, of course, nonsensical if you think about it from the point of view of the air. The air above the wing has no idea that it is supposed to meet up with the air under the wing, so it doesn't.
Let's explore the real physics involved with a real airfoil on a real plane, not in a wind tunnel. We assume for simplicity that the air is static before the arrival of the airfoil, and it's the airfoil that moves horizontally (from right to left), not the air. As the airfoil cuts through the air horizontally, it forces some air near the airfoil downward below the airfoil and the rest of the air initially upward to make room for the airfoil as it pushes through the air.
The weight of the plane on the air under the wing bunches the air up and forces it downward which creates an equal and opposite force on the wing that results in holding the plane aloft against the force of gravity. This dynamic air pressure under the wing retards the air flow beneath the wing, and then gets translated into downward air velocity.
Contrary to the image in the video, the leading edge of the airfoil has to be an area of high dynamic pressure, not low pressure, as the leading edge pushes against the air, causing the laminar air nearest the leading edge to move horizontally with the airfoil and thus to bunch up. The dynamic pressure gets immediately translated into air velocity away from the high pressure area and the leading edge of the airfoil since the air is not confined to a vessel.
The area of low pressure occurs not at the crest of the camber as depicted, but further back along the airfoil where the airfoil tapers downward, dynamically creating an area with no air (vacuum) immediately above it that causes air above the airfoil to be sucked downward and follow the curve of the airfoil down (review the Coanda effect). An airplane may stall if the angle of attack is too great, causing air to fill the vacuum from behind and below the airfoil instead of above it.
Note that the airfoil's horizontal movement results in net downward movement of air both above and below the airfoil (at the trailing edge) and there is no actual horizontal movement of the air opposite that of the airfoil. Instead, some drag inducing air is actually displaced in the direction of the airfoil movement.
If we insist on using Bernoulli's principle to understand airfoil design, we must understand that the dynamically generated high pressure at the leading edge of the airfoil induces downward, and also some upward and leftward velocity on the air as the airfoil pushes from the right and blocks rightward air movement out of the high pressure zone. The weight of the plane also adds to the dynamic pressure under the wing and increases downward air velocity, but it's that air pressure that holds the plane aloft. The dynamic pressure under the wing also displaces the air to the left relative to the air above the wing, retarding it in its traversal of the airfoil. At the upper rear of the airfoil, the dynamically generated low pressure (vacuum) induces downward and possibly rightward and upward velocity to the nearby air of relatively higher atmospheric pressure so that air pressure is quickly equalized in the wake of the airfoil.
I didn't refer to the "longer path theory"/"equal transit time theory" in the video. I just said that flow above the wing is faster than flow below it, without explaining why. The author of the page you linked to above states that there's nothing wrong with using Bernoulli's principle in the context of explaining lift. They refer to the circulation theory, which can be used to explain where the difference in velocity comes from, and so combined with Bernoulli's principle provides a more complete explanation of lift. I plan to cover this in more detail in an upcoming video.
I agree with you on every part in this video except the one at 5:09: whilst Bernoulli's theorem that high-velocity results in a decrease in pressure is, in fact, correct, it is not the reason how *lift* is on an airfoil, such as a wing on an *aeroplane* is created. This is due to *Newtons third law* _actio = reactio_ as the deflection of the air above the airfoil creates an opposite reaction. This reaction force allows the wing to create lift. I mean: imagine that it would, in fact, be Bernoulli's principle that was responsible for the creation of lift. What, if an aeroplane would fly upside down (like an aerobatic plane)? Or what about wings, that are symmetrically formed? Also: there is an old theory, that air velocity over an airfoil would increase to reach an air particle from under the wing at the end. This theory is also wrong and visualised in this video from Cambridge University: ua-cam.com/video/UqBmdZ-BNig/v-deo.html
You're wrong, it takes both Bernoulli's equation and Newtons third law to explain how lift is created by aircraft.
@@jaffacalling53 Maybe it takes both principles but it is wrong the way the video explained the lift generation.
@@leonardocortezgonzalez9043 Yes, the video oversimplifies it to the point of basically being wrong. But both effects need to be considered to fully explain how lift is generated.
I see that you both have already discussed the point of my comment. Yes, it is clear to me that Bernoulli’s theory is not wrong per se but just too oversimplified in the video to use it alone to describe the lift effect. It’s just that I have learnt in my physics course, that Newton’s third law would be more relevant for the creation of aerodynamic lift than Bernoulli. I guess it’s still a topic of discussion how much either principle is more or less relevant, as personally, I do in fact believe that it is actually Newton’s third law. This is because - as stated in my previous comment - how would lift be produced if an aeroplane flies with symmetric airfoils?. I really don’t know how that could be explained with sticking only to Bernoulli.
And just as a disclaimer: I actually said that Bernoulli’s principle is not wrong in its actual meaning, but, yes, I guess I should have been a bit more precise that I meant that lift is not only a result of Bernoulli’s principle but also Newton’s third law rather than just focusing on Newton after that.
Actually it's just another way of describing what's going on. In physics there are often multiple approaches to understanding and analyzing a system. In the case of lift there is in fact an air velocity/pressure differential (and you are correct that the old hypothesis that this pressure differential came from particles "splitting and meeting" across an airfoil is entirely wrong) between the top and bottom of the wing and that pressure differential can generally account for the lift, or at least most of it. Newton's laws also apply of course, but instead of analyzing by pressure differential you would analyze by the mass and average downward velocity of the air coming off the airfoil. In the same vein you can analyze the system through conservation of energy. Now if you want a deeper understanding of what's specifically going with the air at and behind an airfoil, you have to have a more advanced understanding fluid dynamics including both turbulent and laminar flow. The way airfoils generate vortexes is particularly critical.
As for flying upside down, that has to do with getting different results out of an airfoil with different angles of attack. Aerobatic planes in particular are generally made with symmetrical airfoil wings so that performance with negative angles of attack can more or less mirror positive angles. Some asymmetrical airfoils can still fly upside down but will perform very differently at negative angles than at positive angles and are therefore less predictable for the pilot when the plane is inverted.
The most valuable goldmine for engineers in the entire youtube
I really enjoy and appreciate your videos. If you could do a video about tolerances-fits that would be amazing. Thank you and keep up the inspiring work.
Your method of explaining is beyond awesome. I wish college used the same methods of explanaition.
Excellent illustration, very well explained. Recently came across this channel and saw a few videos about fluid mechanics as it is what I am studying rn and the grasp of ideas and concepts I had after watching these videos is just crystal clear. Thank you soo much :)
video graphics are insane , thank you making such a high quality content.
Fluid dynamics Chapter 1:
"Water flowing down the gully
it's adhereing to Bernoulli"
I watched this video before fluid mech lecture. Now I am studying it that's why I understand your video clearly. its satisfying.
i don't think i intuitively understood bernoilli's principle, even after a college degree in engineering until this video.
college is so worthless.
good teaching/schooling/education is all about how well you're able to get a person to have that aha understanding, not how much money it gets, its brand name reputation, or how challenging they make their courses.
im doing a report on this topic and everything youre saying is 100% true bc so far im 15 pages in and i barely know wtf im doing
@@alieneater3328 so how'd that report go?
@@yngfljm2277 went well. actually understood what i did eventually and submitted it.
Thanks
About this channel :
In One word - Great.
Can tell me the source - books for Fluid Mechanics and Strength of Materials?
keep making great vids like
centrifugal force , pascal law , continuity equation , venturi , orifice , water hammer , stall , detonation , surge , knocking , stagnation pressure , vibration , cavitation
we all be really grateful if you did those
Very neat and clear explanation sir, but I just can't help but miss your videos on structural mechanics. Hope one day we will see some lectures on macro-mechanics of composite materials from you. Keep up the good work!
ua-cam.com/channels/gnO_q7xjxSYotvyUMgwzEA.htmlvideos
Learned about Bernoulli’s Equation in my ODE class a week or two ago. Thanks for helping out w the visualization
Hats off to you sir.! You are also a great personality to witness sir. Though you don't mention in your videos but I do get motivation and inspiration at the end of the video to try to follow your path.!
Sir, can you please explain why for an airfoil you represented the low pressure with a much more area diagram than for pressure below airfoil, is it a free hand type of pressure diagram?
Thank you sir for your videos & presence again.!🙏
To be pedantic, 0:50, Bernoulli did describe it, but it was Euler who derived the equation in the usual form.
I think Bernoulli's equations play a minor part in wing lift, and the main emphasis should be directed toward Newton's Third Law of Motion which says for every action there is an equal and opposite reaction. If a plane's wing is being pushed up, then the equal and opposite reaction is air being pushed down.
Airplane wings are usually tilted upward in front by four degrees, which creates more force on the bottom of the wing than on the top surface, thereby creating a tremendous upward force on the bottom of the wing producing lift. I seriously doubt the additional small amount of distance the air requires to travel over the top of the wing surface creates a pressure differential large enough to produce the necessary lift.
I think u are not able to make the connection between these concepts... Actually it is interconnected...
I.e. the shape of the wing and the tilt contributes to the low velocity... The key here is reducing the velocity below the wing which cause not just the drag and lift effect but also increase in pressure below the wing span... Which mean relatively higher velocity and lower pressure in the upper wing portion...
@@deepaksubba9527 - I perfectly understand the interconnectedness of the principles involved. I am just stating that Newton's law is the predominate issue here.
@@cwj9202 I agree about Newton's Third being important but the pressure differential can't be underestimated. The pressure differential is not just dictated by the thickness of the wing but by the difference in boundary flow conditions on the upper and lower portions. The flow is much more turbulent on the upper portion (the 4 degree tilt mentioned ensures this) resulting in a significant increase in velocity and corresponding decrease in fluid stagnation pressure on the upper portion relative to the lower
@@ilovekianna21111 --- I will not disagree with the physics you mention, but I think they are minor in comparison to the principles of Newton's third law of motion.
@@cwj9202 I dont understand why bernullis principle is always used to explain wing lift eventhough newtons ? law is so much easier to explain( and isnt countrrintuitive to many people as decreased pressure st higher speed is) also it doesnt explain lift from symmetrical airfoils
Educational videos like this are life savers for high school students like me during this period of uncertainty.
There are moments in life where you must pause to digest something new that contradicts your intuition.
4:30 is one of those moments
That's why they call it a paradox for a reason. :)
These are the best graphics I have ever seen in UA-cam superb bro
Keep going
Great video and animations as usual. Thanks a lot. A questionn about the Pitot tube : Why do you assume that the flow doesn't enter in the tube ? In an other words, why do you assume that the stagnation point is at the entry of the tube, rather than at the end of it, where the stagnation pressure measurement takes place ?
This video is WAY BETTER (in my opinion) than some high standard textbooks ! This is really a great job ! Thank you !
Civil engineers here ✋
I have a daily homework on this topic on Sunday. I did not understand this topic, but when I watched this video, I understood a little of it 😂👍 Because the language you speak is not my mother tongue.
شكرا❤
I spotted a mistake. At 3:30 you say that the continuity equation is valid under hypothesis of incompressible fluid, which is wrong. The right hypothesis for the continuity should be the steady state condition. Nevertheless, excellent job! Keep up the good work!
3:37 I think there might be a mistake in the script. Mass flow rate stays constant regardless of compressibility. Nozzle calculations for compressible fluid ride on the fact that mass flow rate is constant regardless volumetric flow rate.
At the end of the lecture in which he introduced Bernoulli's equation, my Fluids professor said, "just remember, what goes in that end has to come out this end."
Easy peasy.
nice
You are a hero. I love your videos so much! watching this video is more enjoyable than watching movies
Which software you use make such video ?
9:30 the same as expression for calculating the final velocity of a particle on free fall!!
I just had the exam in fluid mechanics and this pops up right after lol. Good video nevertheless!
Hope it went well!
@@TheEfficientEngineer Thanks. We'll see after I get results 😃
@@TheEfficientEngineer Went well. I passed, now I have this video to help me for oral examination. Thanks!
love how you explained everything.
Would you consider creating a video on your process in Blender for these videos? Or link some resources you used to develop your skills in this area? I am a young lecturer at a university and I want to build up my own catalog of content like this, I've shared your videos with my students and they love them!
Hi Jon, thank you for sharing the videos! There are many Blender tutorials on UA-cam which explain the software far better than I ever could, so I haven't planned on creating any such videos myself. I talk a bit about my specific workflow on my Patreon page (www.patreon.com/posts/36136936), but feel free to email me at hello@efficientengineer.com if you have questions or anything you would like to discuss.
Where has your channel been all these years. So glad to know I've found another great UA-cam Channel. Thanks🔥
thank uuu very much for videoss ...they are simply awsome..
being a neet aspirant its really difficult to understand concepts of physics this video i found randomly on clicking today and as my visual power is good i understood the whole of it in just 13:45 time. .keep it up @the efficient engineer😇😇☺
I am glad that how most of the people here are INDIAN. BTW I am also preparing for JEE.
@@7_thala_for_a_reason 👍👍👍
11:04 fun fact about those 3 assumptions is that all 3 of them are, technically, not true.
They're 'usually close enough to being true so it doesn't significantly impact the outcome' but they are never, *EVER*, 100% true.
And thus it's important to realize that Bernoulli's Equation is, at best, an 'estimation'.
For a tool, that's perfectly fine.
We’re engineers, we only depend on real world application. So it not being 100% doesn’t really matter as there is a margin of error in every real world tool.
@@markjones6894 Very true.
I just found it important to point out because in the video I didn't get the feeling this VERY IMPORTANT aspect of engineering was being properly covered... half of engineering is balancing the margins of accuracy of equations against the margins of accuracy of material properties against the margins of accuracy of operating conditions against the margins of intelligence of the intended users etc etc etc... It's all just a juggling act really. XD
@@ayporos Everything in physics is an approximation. You can never model the real world 100%, it is just too complex.
@@jimsagubigula7337 That's incorrect. The law of conservation of energy is absolute, and that's just the first one I can think of off of the top of my head... the WAY in which energy is conserved might be difficult to measure as it can transform in different kinds but the law that all of it is conserved is absolute as far as I'm concerned.
@@ayporos Yes, of course. The laws are absolute, the way we calculate things is approximate.
Working on a non Newtonian fluid flow problem right now. Sometimes you just need to get back to basics to figure stuff out. Thanks for the video.
5:08 is wrong. It’s Newtons third law that is responsible for lift of a plane!
sucker it's the same thing
It's a same thing as alt maniac has said...
Magnus effect can also be explained by newton's laws and bernouli principle.
Bruh watch video from 5:08 to 5:30. In this time span he explains how is the force created in the first place which is by the Bernoulli’s principal. Then you can apply 3rd law that the force (whose creation is exolained by bernoulli’s principle ) push air down which result in pushing wing up