Recent content by OldStudent0382

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    Decay of sinusoidal velocity wave (kolmogorov flow)

    Would this be approached similarly to unsteady couette flow? I spent a few more hours trying to research the problem (and the topic) and I'm either not finding anything relevant or I'm just so far lost that I'm not finding the connection between this assignment and what I've been reading.
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    Decay of sinusoidal velocity wave (kolmogorov flow)

    Homework Statement Find the velocity field u(x,t) Homework Equations \rho = constant u(0,t)=0 u(0,L)=0 \frac{\partial u}{\partial t} = \nu \frac{\partial ^{2}u}{\partial x^{2}} u(x,0)=U_{o}[sin(\frac{3\pi x}{L})+0.7sin(\frac{9\pi x}{L})] The Attempt at a Solution I have absolutely no idea...
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    Fluids - Squeezing flow - How to find force, work, and flux

    Should I be replacing "H" with either the function "H(t)" or z? At first I thought it should be the size of the initial gap or distance from z=0 (in this case, 1cm), but I'm starting to question if that assumption was correct. For the volumetric flux Q(t), would it be the circumference of the...
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    Fluids - Squeezing flow - How to find force, work, and flux

    In addtion - for work, would taking the work done by 1 piston and multiplying it by 2 provide a valid answer? or even just integrating from -1cm to +1cm would provide the same result as integrate from 0 to +1 or -1 and multipling by two, I think. I always doubt myself on these situations and...
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    Fluids - Squeezing flow - How to find force, work, and flux

    Thanks - I wasn't too sure about H(t). As for where you said the 4 should be an 8. Here's how I got it: F=\int_{0}^{R}[\frac{3 \mu V}{4H^{3}}*[2z^2+R^2-r^2]]*2\pi r dr becomes: F=\frac{3\pi \mu V}{2H^{3}}*[z^2 r^2+\frac{R^2*r^2}{2}-\frac{r^4}{4}] Then substituting in R: F=\frac{3\pi \mu...
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    Fluids - Squeezing flow - How to find force, work, and flux

    Here's what i meant to enter earlier: F=\frac{3\pi \mu V}{2H^{3}}*[z^2R^2+\frac{R^4}{2}-\frac{R^4}{4}]+\pi P_{o}*R^2 Besides replacing "z" with H, Is Po the only correction I need to make? Just dropping it? In thinking about the problem, I had a feeling it would cancel out. For work, would I...
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    Fluids - Squeezing flow - How to find force, work, and flux

    Homework Statement The initial separation of the pistons is 2cm. They are submerged in water at room temperature. I need to calculate the work required to have two pistons touch, find the volumetric flux of the water as a function of time, and the force at a given time Homework Equations...
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    Fluids - Darcy's Law, permeability of a filter

    Dividing by (1.8d)^2 gives \frac {Q}{A} = \frac {\pi*d^4}{128u} * \frac {Δ P}{L} * \frac {1}{(1.8d)^2} which reduces to \frac {Q}{A} = \frac {1}{32*1.8^2} \frac {\pi*d^2}{4} \frac {1}{μ} * \frac {Δ P}{L} Would k just be this part?: \frac {\pi*d^2}{414.72} I also tried taking the ratios of...
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    Fluids - Darcy's Law, permeability of a filter

    I can't edit my last post, so I'll add a new reply: I found: k=Vavg * μ * L/(ΔP) Am I on the right track or am I a lost cause?
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    Fluids - Darcy's Law, permeability of a filter

    taking the integral of the velocity profile * area I get: Q=∂P/∂z * π*R4/(8*μ) -> (|ΔP|/L)*π*r4/(8*μ) Thanks for all the help -- this already has been far more than I expected to receive.
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    Fluids - Darcy's Law, permeability of a filter

    Thanks -- the equation given in the problem is the same one in my professor's handouts and what he gave in the lectures (and of course, this was rushed in the last 5 minutes, so he couldn't go over a problem). I know this should be a really easy problem and I'm just getting hung up on something...
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    Is it Worth Going Back to School for a Career Change in Engineering?

    Studied ME in undergrad and didn't take it seriously -- I started a business while in college and to be fair, it was worth the abysmal GPA. After undergrad, I kept my business going and worked in IT making a pretty good salary. I wasn't happy and dreaded every morning. Saved up some money and...
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    Fluids - Darcy's Law, permeability of a filter

    Homework Statement Derive an analytical expression for the permeability (k) of the structured porous medium (which is a size selective filter) constituted by a periodic array of cylinders of diamter d separated by a distance h = 1.8d Homework Equations Q=k*(μ/A)*(Δp/L) Q = volumetric flow rate...
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