Fluid Mechanics: Topic 7.2 - Conservation of linear momentum for a control volume

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[@Nayan133]

I've learned - 1. The net incoming & outgoing momentum fluxes & change of linear momentum throughout control at any instant in time contributes to external unbalanced forces. 2. The external forces acting on control volume is by two ways - Body force & surface force. Body forces are gravity forces & other forces like magnetic, electric, etc. Surface forces are pressure & viscous forces. These all forces combines to responsible for the net change in momentum of control volume (Volumetric change as well as fluxes through boundaries). 3. Momentum transport equation is application of Reynolds transport theorem in which flow of mass carries & transports a property with it - Velocity. 4. Momentum fluxes are used as an averaged over those respective cross sectional surfaces with correction factors to compensate from actual momentum fluxes at those cross sections. 5. For each control volume, the momentum conservation equation is written on unit volume basis. As the system is considered to be open system if there is transport of both mass & energy.

[@sunshinecherries]

this explains very clearly what my professor could not, thank you very much 😂

[@IngeNacho]

Excellent video. Perfect explication. In my lenguaje y can't found a video better than this

[@jacqueline8805]

Incredibly and extremely well explained. Thank you!

[@CPPMechEngTutorials]

Glad it helped!

[@sly4u247]

Thank you so much, do you have videos on continuity equation?

[@pratapchoudhari]

Blessed to have such crystal clear explainantion. Thank you very and keep going. :-)

[@CPPMechEngTutorials]

Thanks!

[@kephamatoke5249]

Lecturer at JKUAT UNIVERSITY kenya. Found the presentation excellent and resourceful. Congratulations to DR. PAUL NISSENSON

[@CPPMechEngTutorials]

Congrats to him!

[@atakan716]

Very clearly explained :)

[@CPPMechEngTutorials]

Hooray!

[@ishakaimen1576]

Thank you for downloading these videos. I want to ask why we don’t see A correction factor in the conservation of Mass video?

[@CPPMechEngTutorials]

None is needed.

[@artemrusskikh2796]

Does all the time external foces acting on the system are the same as the external forces acting on the CV? If not, can you equate Reynolds transport theorem for extensive property of the system to external forces action on CV? (1:24-2:08)

[@CPPMechEngTutorials]

Our goal is to obtain a conservation of linear momentum equation for a CV, but the conservation law is usually expressed for a system. The CV is set up so that it completely coincides with the system at a particular time. This allows us to apply the Reynolds transport theorem (RTT) to relate the CV and system points of view. If we wait long enough, all of the mass (system) will leave the CV, but we don't care about that. We only want the expressions that relates the time rate of change of linear momentum from the system point of view, to the time rate of change of linear momentum from the CV point of view.

[@dudley-awilliams723]

Womderful

[@is-ig4zh]

Thank you, sir!

[@CPPMechEngTutorials]

No problem.