Fluid Mechanics: Topic 6.2 - Reynolds transport theorem

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[@aliibrahimshabrawy6745]

I wonder why B1(t) = B11(t) = 0 you say that it doesn't exist yet but how can this be possible isn't region 1 and 11 have fluid so where there is a fluid there must be a property for it this is how i think if there is something wrong i want to know what is right?

[@CPPMechEngTutorials]

Initially the system and control volume coincide at time t. Regions I and II have zero volume at this time, so they do not have mass (or any other extensive property) yet.

[@srimanvallakatla6030]

at time t B1 is not equal to 0 i think sooo

[@CPPMechEngTutorials]

The volume occupied by region 1 is zero at time t. If there is no volume, all extensive properties are zero within the region.

[@pro.navalarchitect]

How is volume occupied by region 1 is zero at time t ??

[@CPPMechEngTutorials]

If you look at the image at time t, there is no B1. B1 is the region in which new fluid flows into the CV. So some time needs to pass (for example, time dt) in order for new fluid to enter the CV.

[@DP-sq7lw]

What a beautiful video!! I love it! Beautiful theorem with a great explainer!

[@Driftking009]

You saved the value of my degree man, thanks!

[@waleedkhan8590]

This has to be the best explanation of RTT ! And that too in a little more than 15 minutes. Amazing. Thank you!

[@lamarjacksonallah1005]

ozan ozcan benim lan!!!!!

[@furquanmohammed3086]

Sir, At 10:38 while deriving the value of B' in should there be a negative sign since after taking after the dot product the whole value would be negative anyways, and initially when we said B'(out)-B'(in) are we not just considering their magnitudes only. and its exactly same as B'(out)+B'(in) when considered them as vectors. the result does not change anyways

[@adriangonzalezsuaret9368]

You are the best, I learn a lot with you. Thanks!!!

[@CPPMechEngTutorials]

More videos are development. You will be able to learn a lot more soon. :)

[@shailendrarana4073]

Beautifully explained !

[@j.gordonleishman6401]

Very nice explanation. A little robotic narration in places, but one of the best explanations of the RTT I have seen in 30 years. Well done!

[@CPPMechEngTutorials]

Beep bop boop

[@ozzyfromspace]

That was a brilliant video! So well explained!

[@CPPMechEngTutorials]

:)

[@arijitsaha1472]

Clean explanation leads to a better understanding and that happened with me. Thanks for sharing the information. But I have a doubt and that is why are you considering dB=b*rho*dA*dLn whereas the dV considered is in the direction of V vector?

[@robertoneto6984]

What an awesome video! Quick question. You said that the inflow region of the CS is AFC and the outflow region is ADC, but AFC and ADC are 2d curves and not 3d surfaces. Shouldn't the inflow and outflow regions be 3D surfaces, since they contain a volume (and not an area)?

[@prabhakartripathi4474]

While factoring out mass, you have written m=m(1), why you considered (1) as intensive property? Please do explain.

[@fourier07able]

BTW, mass ``m'' is not a property neither ``extensive'' nor ``intensive'' since it is the connection: B=mb, where ``B'' is extensive and ``b'' is intensive properties. For example, pressure and temperature are not neither intensive nor extensive, although they are properties of any (thermodynamical) system. On the contrary, the specific volume v=V/m is an intensive property of the system (open or closed!).

[@siddharthprakash8942]

Brilliant video. Gave me a very clear picture. Thanks a lot

[@CPPMechEngTutorials]

Our pleasure.

[@BTCIVSangharakshitKadam]

@@CPPMechEngTutorials Explained very nicely thank you.

[@nidalal-sayed4019]

Plzzz help me: I am trying to remember a theorem that study the movement of water particles. This theorem compasses two parts one is real and the another is imaginary part. If you know plz reply by the name of theorem or if you have a video share here as a link because I am tired from searching a video about this

[@tabishkhan3094]

Can we get these notes written somewhr

[@drelina1938]

Thanks very well ! Good Exceptional

[@surryyaanjum8275]

Good explanation ❤

[@ahmadahere3679]

These videos are spectacular. They are helping me refresh and prepare for courses in my graduate program. Is it possible to get ahold of the slideshow material? I can't find any lecture slides of this calibur on this topic.

[@CPPMechEngTutorials]

At the moment, the slides are provided to students enrolled in certain sections of ME 311 at Cal Poly Pomona. We do not know whether the slides will be available to the general public in the future though. However, the videos will remain on KZbin for the foreseeable future.

[@trololollolololololl]

Grad program? We got it in undergrad first sem of second year :/

[@mymathmates4409]

Very good defined..go on..

[@siavosheskandary2866]

thank you it was very helpful

[@nabadas8085]

nice explanation,Thanks a lot

[@martinjosealvarez]

Thanks from Mexico

[@atakan716]

Awesome indeed!

[@muhammadmehran7173]

sir can u send this slides

[@alejandroarias473]

Are there any videos of concepts and derivations but for thermodynamics?

[@CPPMechEngTutorials]

We have thermodynamics videos at www.cpp.edu/meonline

[@alejandroarias473]

@@CPPMechEngTutorials Thank you very much

[@anjumshahzad78]

great explanation

[@mrunaldharbathula9872]

excellent work...….keep going

[@CPPMechEngTutorials]

We will.

[@DipayanPyne]

The momentum of a system is conserved only when there is no net external force on it. The same is true for energy w.r.t a given system. So then dont you think the laws should not really be named as 'conservation' laws ? I mean I do understand the idea behind these laws, but the term conservation sounds a bit misleading, isn't it ? For eg: If the property under consideration is the mass of the system, we know that it doesnt change over time, coz the amount of matter in the system is fixed, as the system has been 'identified'. So the term on the LHS of the RTT drops to zero and we then rightfully say that the mass is 'conserved'. But the same is not always true for momentum or enery of a system, as they often change, given a net external force or an energy transfer. What do you think ?

[@mohammadabedy2478]

perfect teaching , thanks for video

[@CPPMechEngTutorials]

Thanks!

[@belisariogonzalez7793]

When will Biddle's ME415 lectures be posted?

[@CPPMechEngTutorials]

+Belisario Gonzalez Probably by F2016. They are still in post-production.

[@CPPMechEngTutorials]

Update -- The ME 415 videos likely will be available by early W2017.

[@saimsiddiqui1544]

Very good

[@paulboughosn6174]

thank you !

[@joyaljoshi5073]

Why is at time t, B1(t)=0

[@bacharobeid7430]

perfect

[@mohibahmadsiddiqui659]

Amazing.

[@CPPMechEngTutorials]

Thanks!

[@raymond-andrade]

Thanks, this helps

[@CPPMechEngTutorials]

Great!

[@timnguyen1329]

4:20 , I confuse that what region is for Bcv(t+dt) , thanks!

[@CPPMechEngTutorials]

The CV is fixed, so Bcv(t+dt) is the amount of B (mass, momentum, or energy) within the red dashed line at time t+dt. This can be different that the amount of B in the CV at time t. For example, let's say B is mass and imagine a denser fluid enters the CV in region I during time dt. In this case, Bcv(t+dt) > Bcv(t).

[@aliallaou4415]

Thank you very much

[@CPPMechEngTutorials]

We're glad the video helped.

[@amandadube156]

Thanks!!

[@CPPMechEngTutorials]

No problem

[@Inamullahkhan6294]

Excellent

[@CPPMechEngTutorials]

Glad you like the video.

[@viclopez5363]

Excelente!

[@CPPMechEngTutorials]

Gracias!

[@viclopez5363]

Muchas gracias!

[@ANKITKUMARchb-gn7xc]

nice video

[@CPPMechEngTutorials]

Thanks

[@sourabhyadav2363]

India se h koi

[@usernumbereighteen]

why did I choose engineering

[@ranajitmajumdar7836]

nice 1

[@CPPMechEngTutorials]

Thank you.

[@allandavis6116]

I think the eq. at 4:43 should read Bcv = Bi + (Bsys-Bii) which you rearrange to Bsys = Bcv - Bi + Bii

[@acruzp]

I don't concur with my peers, I think this is a lousy explanation: It would be much better if you started out by giving an intuition of what the theorem attempts to solve, a general picture if you will. Then, if your objective is to impart a working, operational understanding of the subject, you can progress in the way you did. I would, though, prefer if, at every point, you stopped and explained where you're heading and why.

[@CPPMechEngTutorials]

Follow-up videos show the application of the theorem to derive conservation laws for control volumes.