Physics: Fluid Dynamics: Fluid Flow (1.5 of 7) Bernoulli's Equation: Unknown Velocity

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  • Опубліковано 2 гру 2024

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  • @gets0410
    @gets0410 7 років тому +27

    Best lecturer on UA-cam.
    Currently *Reviewing* for my Engineering exam.
    Thank you for these videos, they're helping me a ton.
    And your website's great, too.

  • @HoudiniHamster
    @HoudiniHamster 2 роки тому +8

    I am not english native but your diction is so clear that it's a pleasure to hear you. Thank you.

  • @fiaadalli4309
    @fiaadalli4309 4 роки тому +3

    If I had this guy as a prof, I don't think I would struggle learning this material. Well done.

  • @leemontgomery7914
    @leemontgomery7914 4 роки тому +3

    Appreciate how this professor teaches/instructs. Wish I had had him for fluid mechanics/dynamics. He teaches “practical” real world problems and not theory. Bet this professor knows how to install sprinkler systems ( this is a complement). Good job professor!

  • @Munneh
    @Munneh 4 роки тому +12

    Thank you for these free videos, you've helped alot of students!

    • @MichelvanBiezen
      @MichelvanBiezen  4 роки тому +6

      We are glad these videos are helping students around the world

  • @ptyptypty3
    @ptyptypty3 7 років тому +18

    well done MICHEL!!.... by the way, it's amazing the difference in your Videos now. I'm referring to the HIGH DEF and the Brighter Lighting.... Your videos are so CLEAR!!.. Congrats!!.. Currently I'm following your Videos on the LINE INTEGRAL... I've always wanted a clear understanding of that. So far I'm through video #4, your latest... Thanks for all you do!!.. I trust your summer is going well and you're enjoying some Fun Time.... now it's back to more learning.. .. ....

    • @MichelvanBiezen
      @MichelvanBiezen  7 років тому +11

      Hi Philip,
      Yes, we have learned a few tricks of the trait over the years. We really didn't know what we were doing in the beginning. The series on line integrals were fun to make. Believe it or not, we are learning as well. I remember many years ago doing these line integrals without actually knowing what they were or what the represented. That is why we made video # 4 to contrast it to what people think they are. There is some interesting revelations on line integrals coming up later in the series.

  • @rommelevangeliovallejo8328
    @rommelevangeliovallejo8328 3 роки тому +6

    The explanation is clear and precise. New subscriber here

  • @shantosiddique1050
    @shantosiddique1050 4 роки тому +2

    I used flowrate formula to find the v2
    got the same answer and way easier I guess
    love your videos.

  • @shivendra18
    @shivendra18 7 місяців тому +1

    You are a great teacher you explained it very well
    Lots of respect to you from India 🇮🇳

  • @golo5000
    @golo5000 4 роки тому

    You make Bernoulli's equation simple to understand.

  • @consumerelitist6508
    @consumerelitist6508 4 роки тому

    Thank you Mr. Biezen. I Favorited this video. Now I just need to figure out how to incorporate 2-90deg bends. It is just like the diagram you have shown here except those two curves are 90 degree elbows. I'm going to watch the rest of your videos.

  • @jesstinmarkie1512
    @jesstinmarkie1512 3 роки тому +6

    Sir, what if there is no given velocity, how would you calculate the velocities in the narrow part and in the other part of the pipe? Ty

  • @kannathasank9629
    @kannathasank9629 3 роки тому +1

    yeah, I appreciate your teaching method. We learned

  • @godwinnaaba1855
    @godwinnaaba1855 6 років тому +1

    it's cool. I got the understanding perfectly. thanks

  • @annamoulds5010
    @annamoulds5010 Рік тому +1

    These videos helped me so so much! Thank you :)

  • @biancaciocirlan8527
    @biancaciocirlan8527 5 років тому +1

    great explanations !!!! helped a lot, thanks!!

  • @Duck-jc9ox
    @Duck-jc9ox 6 років тому +2

    Great lecture. Thanks so much!

  • @jameskiwic3987
    @jameskiwic3987 Рік тому +1

    this man is master didact, i just understood constraint based solvers by watching this (at least i think so😅)
    thanks for your work
    if i may suggest something, maybe make the connection to conservation of energy and or kinematics? you have two very nice terms in your equation which correspond to kinetic and potential energy 🤔
    Edit: he made the connection in a later video

  • @esronsimangunsong8155
    @esronsimangunsong8155 3 роки тому

    Thank you Mr.Biezen

  • @mmenjic
    @mmenjic 3 роки тому +1

    7:49 but from where does this additional pressure comes from ?
    If we had 1 bar at point 1 this could get the water in the vertical pipe to approximately 10m, can we now take 7000 times wider pipe and get water to 1 kilometer in vertical pipe and still have 1 bar at the point 1 ?
    Or in the previous example, if pipe is constant diameter and height difference is 1000 meters and pressure at the point 1 is 2 atmospheres, I bet there would not be any water at the point 2 ??

    • @MichelvanBiezen
      @MichelvanBiezen  3 роки тому +1

      Making the pipe wider will not cause the water to go higher with a particular pressure.

    • @mmenjic
      @mmenjic 3 роки тому

      @@MichelvanBiezen so pressure is not higher in wider pipe ?

  • @omidkhalili6754
    @omidkhalili6754 3 роки тому +1

    The Best Ever Thank You...

  • @anilkumarsharma1205
    @anilkumarsharma1205 5 років тому +1

    kya atmospheric pressure sey energy bana saktey hain, tum burnouli equation ko jantey hain ho to heron's fountain and siphon and heron's fountain formula and inverted siphon and siphon and boyle flasks equation ko bhee compare karo
    hindi language means hindi film dekhtey ho to samajh jaogey

  • @hirunrashentha1082
    @hirunrashentha1082 4 роки тому

    Thanks alot sir i learned many more things from your videos 👍👍

  • @thilatem9759
    @thilatem9759 8 місяців тому +1

    Thanks you so much for Good presentation

  • @TaiWills
    @TaiWills Рік тому +1

    Best explanation

  • @princenawal
    @princenawal 5 років тому +1

    Does the pressure drop of the system matters? let say for the same problem in the video, assuming fluid transfer is via hose and it is given that the hose pressure drop is 0.1 bar (or any value).

    • @MichelvanBiezen
      @MichelvanBiezen  5 років тому +2

      Yes, the pressure drop matters, and if the drop is due to frictional drag, then it must be added to Bernoulli's equation. There is a playlist that includes additional terms to Bernoulli's equation: PHYSICS 34.1 BERNOULLI'S EQUATION & FLOW IN PIPES

    • @princenawal
      @princenawal 5 років тому +1

      Thank you!

  • @4hour253
    @4hour253 10 місяців тому +1

    would P2 be 1 atm for most cases? 1 atm resisting the pressure coming out of the tube?

    • @MichelvanBiezen
      @MichelvanBiezen  10 місяців тому +2

      Normally while inside the pipe, the pressure will be greater than 1 ATM, and after it leaves the pipe, the pressure will then be 1 ATM

  • @tongshen6610
    @tongshen6610 6 років тому

    Thank you very much for the series.

  • @cljoulin
    @cljoulin 5 років тому +1

    Hello Michel, thanks for this I really liked it. However, it doesn't seems to work when P1 = P2 = Patm i.e. both ends of the tube are open to the atmosphere.
    Let's say 1 is higher than 2 and fluid still flow from 1 to 2 and let's say I am trying to determine the velocity at point 2
    The Bernoulli equation you get when removing P1 and P2, and multiplying by 2*rho is
    0 = 2g(h1-h2) + v1^2 - v2^2
    If we input v1 = v2 (A2/A1) we get
    0 = 2g(h1-h2) + v2^2 (A2^2/A1^2 -1)
    V2^2 = 2g(h1-h2)/ (A2^2/A1^2 -1)
    I have a problem here when A2 = A1 --> A2^2/A1^2 -1 = 0 and I end up dividing by 0. Also I get infinite speed if A1 and A2 are very close.
    There is definitely an issue somewhere but where is it !?

    • @MichelvanBiezen
      @MichelvanBiezen  5 років тому +1

      You may be setting up a hypothetical situation which violates the laws of physics.

    • @cljoulin
      @cljoulin 5 років тому

      @@MichelvanBiezen I am trying to solve this problem www.chegg.com/homework-help/questions-and-answers/water-tank-water-level-height-h-exposed-atmospheric-pressure-bottom-tank-nozzle-angle-thet-q18940888
      For this, I want to know the speed of the water at the bottom of the tank. I thought this could be solved with Bernoulli's equation by considering a point A at the top of the tank (a large section pipe) and point B at the bottom of the tank (a small section pipe) both are at the atmospheric pressure

    • @cljoulin
      @cljoulin 5 років тому

      This problem is actually closer to what I am after www.chegg.com/homework-help/questions-and-answers/problem-3-water-tank-cross-sectional-area-a1-075-m2-open-atmosphere-outflow-pipe-bottom-cr-q25219741

  • @abigailabigail2196
    @abigailabigail2196 4 роки тому +2

    God bless u sir

  • @-allAboutfootball
    @-allAboutfootball 3 роки тому +1

    Thank u prof Michel 100%

  • @patricknijkamp4736
    @patricknijkamp4736 5 років тому +1

    how about, i have a waterpump which pumps 15 liters/min. with a pressure of 0.35atm.
    the length of the pipe is 2.5m and the height difference is 1m. i have to split the pipe at 0.5m height into two pipes. the total length will be 3.5m now. the diameter of the tubes is 10mm.
    how do i calculate the speed of the water at the top? is it just the total surface to double. or does the fact that 2 pipes instead of 1 pipe to go up that last 0.5m also has effect?

    • @MichelvanBiezen
      @MichelvanBiezen  5 років тому +1

      Assuming we can ignore the effect of viscosity and the effect at the junction, it is simply the total height difference (which causes a shift in pressure) and the total cross sectional area (which has now doubled and thus the velocity is half at the top.)

    • @patricknijkamp4736
      @patricknijkamp4736 5 років тому +1

      thank you a lot ,@@MichelvanBiezen.
      the total height difference is that with or without the double height from the extra pipe, so 1.5m instead of 1m

    • @MichelvanBiezen
      @MichelvanBiezen  5 років тому +1

      It depends on where you are determining the velocity and the pressure. It would be the same point.

  • @b.a.561
    @b.a.561 6 років тому +2

    Where and in which direction does the P2 exactly act?
    Thank you in advance.

    • @MichelvanBiezen
      @MichelvanBiezen  6 років тому +2

      Using Pascal's principle the pressure acts in all directions.

  • @osamaismail8254
    @osamaismail8254 3 роки тому +1

    thank you, great lecture

  • @anilsharma-ev2my
    @anilsharma-ev2my 4 роки тому

    Work done by an aneroid barometer is what per milibar of atmospheric pressure ??

  • @renukapallege5970
    @renukapallege5970 4 роки тому +2

    Thank you.

  • @NilupulieSumanasiri
    @NilupulieSumanasiri 4 роки тому

    I have a problem with a bent in the pipe. When I checked online for tutorials, most problems with bends were solved by Bernoulli's principle assuming that the inlet and outlet heights are equal. And then forces were resolved at x and y directions at the bend. Can you explain why it is assumed? Is this method correct?

    • @MichelvanBiezen
      @MichelvanBiezen  4 роки тому +1

      That is done for simplicity. Just like we ignore wind resistance in projectile motion, to make it easier. But with more advanced fluid motion problem, the loss due to bends in a pipe are included. We plan on adding those types of fluid dynamic theory and problems, but we don't know when we'll have time.

    • @NilupulieSumanasiri
      @NilupulieSumanasiri 4 роки тому

      @@MichelvanBiezen Thank you!

  • @kozintsevful
    @kozintsevful 7 років тому +1

    What if I am given both pressures, radius for both ends, and the vertical distance between point one and two, but no velocities? This is a problem on one of my worksheets and I dont know how to solve it.

    • @MichelvanBiezen
      @MichelvanBiezen  7 років тому +5

      Since P1, P2, rho * g * h1, and rho * g * h2 are known you can move all those terms to the left side and set it equal to C1 (a constant) Then move (1/2) * rho * v1^2 to the right side, multiply both sides by 2 and divide both sides by rho and you get a constant (C) = v2^2 - v1^2 on the right side. And then r1^2 * v1= r2^2 * v2.

  • @ricodegeus1210
    @ricodegeus1210 Рік тому +1

    Soooi... i kinda get it. But how does that work with an upgoing velocity but the pipe is narrower in the middle? I mean the velocity has to come down at the moment it leaves the narrow part, not? (So why doesn't that work on a universal scale? The only thing i can come up with is that the narrowest part of such a pipe is not completely filled with matter, so you can stretch and compress without any real problems. And that then leads me too.... how much would be enough too compress at the smallest part where something before that smallest part has got to give! Am i wrong, and if yes then why. (I get the equasions still it would be nice to have a video. But if not, equasions are fine.
    Thank you for all you already thought me as well

    • @MichelvanBiezen
      @MichelvanBiezen  Рік тому +2

      The pipe is always filled everywhere and the pipe can narrow and widen in different places and the speed and pressure will vary throughout the pipe.

    • @ricodegeus1210
      @ricodegeus1210 Рік тому +1

      @@MichelvanBiezen that part i get, it is even true on niversal scale but...

  • @Divinesview-h7o
    @Divinesview-h7o Місяць тому +1

    Thanks sir 😊

  • @NOBOX7
    @NOBOX7 5 років тому

    Sir i have a great video for you , how to calculate flow velocity when you no the flow rate and diameter of the orifice or pipe. Im having trouble finding a good answer

    • @MichelvanBiezen
      @MichelvanBiezen  5 років тому +1

      Flow rate = dV/dt = v x A where A is the cross sectional area.

  • @jeanlee2
    @jeanlee2 2 роки тому +1

    Thanks, Thanks, Thanks

    • @MichelvanBiezen
      @MichelvanBiezen  2 роки тому +1

      welcome. Glad you find the videos helpful. 🙂

  • @isa_1997
    @isa_1997 5 років тому

    what I can't understand in a two hours class I understand every single word here

  • @kylem6532
    @kylem6532 6 років тому

    Hello Professor Van Biezen! thank you for all your effort and hard work, it's appreciated!! There's one topic that I've been kind of struggling with for awhile and I really hope you can clear it up for me. I always see the continuity equation used to solve for an unknown velocity under the assumption that flow rate is constant. That makes sense to me but the part that I find strange is that when using the Bernoulli equation, if you push the fluid to a high enough elevation, won't the flow rate be zero at some point? If the water does enough work against gravity, won't the velocity go to zero where nothing will flow out of the pipe at the "shutoff head"? Sorry for the long question, I just can't reconcile how the continuity equation can give the velocity at some height above the datum if eventually the velocity can be zero according to Bernoulli. Thanks Professor!

    • @MichelvanBiezen
      @MichelvanBiezen  6 років тому

      You are correct. If the pipe goes high enough, the force at the bottom creating the pressure may not be enough to push the water to that height and the flow will stop.

    • @kylem6532
      @kylem6532 6 років тому +1

      Thanks professor! So does that mean that the continuity equation isn't accurate if used on any significant elevations, like for example, my basement to the second floor sink? Something in there has me confused lol.

    • @MichelvanBiezen
      @MichelvanBiezen  6 років тому +1

      The equation is accurate in all circumstances. Simply use v = 0.

    • @kylem6532
      @kylem6532 6 років тому +1

      Thank you Professor Van Biezen!

  • @francissareglado46
    @francissareglado46 6 років тому

    What would happen if the pipe creates negative pressure means (for this video) that the reference height is so high it creates negative pressure. What would be its physical mean?

    • @MichelvanBiezen
      @MichelvanBiezen  6 років тому

      If the pipe goes to high, the water won't reach there, (unless there is siphoning action).

  • @chetanpundir5730
    @chetanpundir5730 4 роки тому

    What is the pressure of flowing water in pipe....has cross section area A and velocity of flow is v... density is R......
    There is no elevation in pipe...

    • @MichelvanBiezen
      @MichelvanBiezen  4 роки тому

      Have you seen this playlist: PHYSICS 34.1 BERNOULLI'S EQUATION & FLOW IN PIPES

    • @chetanpundir5730
      @chetanpundir5730 4 роки тому

      @@MichelvanBiezen yeah i watched that now a minutes ago... Thank you very much sir ... You are simply amazing ....
      I am working on these parameters to be calculated with the help of water trajectory method .... calculation will be done Via DESMOS. Graphing calculator .....

  • @BurnaBrandon
    @BurnaBrandon 6 місяців тому +1

    But what if v1 is different from V2

    • @MichelvanBiezen
      @MichelvanBiezen  6 місяців тому +1

      If the diameter of the pipe changes, as it does in this example, v1 and v2 will be different.

  • @samiramammadova4942
    @samiramammadova4942 Рік тому +1

    Great !!!

  • @vishnuhari8713
    @vishnuhari8713 Рік тому +1

    Good ❤

  • @timura.7049
    @timura.7049 4 роки тому

    thanks to you

  • @robmce4872
    @robmce4872 4 роки тому

    Thannk you

  • @JsT_1705
    @JsT_1705 2 роки тому +1

    Sir i do have questions.....

    • @JsT_1705
      @JsT_1705 2 роки тому +1

      Water emerges from a horizontal pipe at a rate of 0.5x10^ 3m^ 3/s. Find a velocity of water at a point in the pipe where the area of cross section is 12.6m^ 2.

    • @MichelvanBiezen
      @MichelvanBiezen  2 роки тому +1

      The amount of water flowing through a pipe ever second = A x v (A is the cross sectional area and v is the velocity of the flow). v = A / flow rate

    • @JsT_1705
      @JsT_1705 2 роки тому +1

      Thank you sir you did helped a great 🥰

  • @potpolima
    @potpolima 7 років тому +2

    computing is easy.. the hardest part is how to derive the formulas

  • @giuseppepicone531
    @giuseppepicone531 3 роки тому

    ottimo

  • @buttercupcumbersnatch7842
    @buttercupcumbersnatch7842 7 років тому +2

    =202.600-49000-24000
    =-72797.4
    Shouldnt that be the result?

    • @MichelvanBiezen
      @MichelvanBiezen  7 років тому +4

      In the US a comma "," is just a separator --> 200,000 = 200000 and a decimal point "." is used for decimal places --> 200.000 = 200

  • @zakirmohammed9662
    @zakirmohammed9662 6 років тому +1

    ur my physics teacher dont u know sir ?

  • @Mau365PP
    @Mau365PP 5 років тому

    7:19 lol

  • @godwinnaaba1855
    @godwinnaaba1855 6 років тому

    it's cool. I got the understanding perfectly. thanks