Fluid dynamics of entry flow into pipe.
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Fluids brahs I need help with my rationalization of this problem.
What components of the velocity vector, and what direction to they change in, in the entry region of flow between parallel plates?
Take z-direction to be direction of flow
Take x-direction to be up and down
Wide plates, so y-direction doesn't matter.
I was thinking that velocity would be a function of x and z. The z-component of velocity would change in the x and z direction, and the x-component would change in the z-direction only.
Is that right? I couldn't think of a reason the x-component would depend on the x-direction. Later on it becomes fully developed (v(x)=0). That's why I said it changed in the z-direction, likewise for v(z).
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>tfw you dropped out of school
>after few years you decided to go back
>managed to get HS diploma equivalent
>tfw colleges in my country have age limits for any kind of degree
>including engineering, law, business, !LOLBIOLOGY!1!, any science for that matter
>except maybe Arts
>can't afford to move to another country
Just wanted to tell you guys who are contemplating about rejoining college and pursue higher education, be grateful that at least you arseholes have a choice.
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Yeah, I'm gonna be up front about this.
I'm working on a thin-layer chromatography lab for analgesics. The analytes are aspirin, acetaminophen, caffeine, salicylamide, a standard solution including all substances, and an unknown solution. About a quarter of my class got retardedly high Rf numbers, like .96 and above, for all analytes. The mobile phase was .5% acetic acid in ethyl acetate. The stationary phase was a silica gel. The teacher either didn't quite know what went wrong or wouldn't tell us (she usually tells us). I'm working with the idea that our mobile phase may have been left in an open container too long, leaving the ethyl acetate to evaporate and making the concentration of the acetic acid too high, resulting in a mobile phase which is more polar than is ideal. Is there anything else I should consider?
Forgive the lame joke.
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Eyh /sci/, tough science question here. Not sure I will get an answer but eyh, who knows?
How do you solve a discretized Schrodinger equation on a non-uniform mesh in 3D.
The problem is, if you use finite difference on a non uniform matrix, your resulting hamiltonian is non-hermitiant.
IH. Tan in "A selfconsistent solution of Schrödinger–Poisson equations using a
nonuniform mesh", JAP 1990 gives a solution for the 1D case (pic related), but it just doesn't extend trivially to superior dimension.
Any insight on how to do that?