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bio website dariocortese.weebly.com
location Bristol, United Kingdom
age 25
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Knowledge and understanding are quite different. Only understanding can lead to being, whereas knowledge is nothing but a passing presence in it. (G.Gurdjieff)


Jul
4
comment Does irrotational imply inviscid?
Done, but I have to disagree on your last sentence. A potential flow is one for which only the condition of irrotationality can arise (and not necessarily the incompressibility). To have a stream function it is enough to have just the incompressibility condition (and not necessarily the irrotationality).
Jul
4
comment Does irrotational imply inviscid?
Do you want me to switch in my auto-answer?
Jul
4
revised Does irrotational imply inviscid?
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Jul
4
revised Meaning of angular velocity in a rotating system
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Jul
4
revised Meaning of angular velocity in a rotating system
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Jul
4
revised Meaning of angular velocity in a rotating system
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Jul
4
answered Meaning of angular velocity in a rotating system
Jul
3
comment Rotation of parabola
I edited, maybe this is more clear! Isn't it?
Jul
3
revised Rotation of parabola
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Jul
3
revised Rotation of parabola
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Jul
3
answered Rotation of parabola
Jul
3
awarded  Organizer
Jul
3
revised Can a scientific theory ever be absolutely proven?
I added the tag epistemology
Jul
3
suggested suggested edit on Can a scientific theory ever be absolutely proven?
Jul
3
revised Does irrotational imply inviscid?
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Jul
3
revised Does irrotational imply inviscid?
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Jul
3
answered Does irrotational imply inviscid?
Jul
3
comment Does irrotational imply inviscid?
I retry to formulate my question and give a possible answer : for irrotationality I have laplacian of the velocity equal to zero, so that I can just write the Euler equation, no matter the viscosity. If the fluid is even quasi-inertia-less, I neglet the inertia term (this is an approximation that must pass through the density and characteristic lenght and velocities) , and I get $\nabla p = \boldsymbol 0$, which is the actual low-Re irrotational equation.
Jul
3
comment Does irrotational imply inviscid?
At first, thanks for the answers. Actually, this was the reason I took the 2D case (K.theorem) "However, in that case you typically want to preserve the viscous term." I can't, because the laplacian of $u$ vanishes, and I usually work with low Re flows with the incompressible condition satisfied.
Jul
3
comment Does irrotational imply inviscid?
Yes, clearly. My doubt was about the possibility to have an irrotational flow at low Reynolds numbers. This is possible only if the inertia is neglettable, and this can be only by means of lenght and density, because the viscosity doesn't enter in the eq- of motion for an irrotational flow. Is that true?