Recent content by Daiquiri

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    Next big thing in the aviation iddustry

    I don't think so - not in the civil aviation, at least. Too many risks involved with malfunctioning of said devices.
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    Why does a pneumatic motor run faster on helium than air?

    Hi, here I am again. :) I was overwhelmed with work in the last few days, so couldn't reply. Yes, now I do understand what you intend. And your analysis is correct. If we put the pressure loss due to friction in the equations then - everything else being equal (piping, pressure difference...
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    Why does a pneumatic motor run faster on helium than air?

    Well, no... dm/dt and R are independent values. The mass flow of a gas (dm/dt) is decided by you. For example, you can control it with a ball valve, which can be set more or less open. R is a physical property of the gas used, and you have no control over it (if not by choosing another gas).
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    Why does a pneumatic motor run faster on helium than air?

    Not really. :) Let's carry on from the second equation: dm/dt = f * rho * V0 where: dm/dt = mass flow of the gas V0 = motor displacement f = frequency of rotation rho = gas density (0.176 kg/m3 helium; 1.225 kg/m3 air) If you want to see the pressure in this relationship, the easiest way is to...
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    Next big thing in the aviation iddustry

    Remotely controlled unmanned flights with neurobiofeedback to the ground-based human pilot.
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    Simplify to find theta, my brain is fuzzled from to much work today

    It's a simple quadratic equation a*x^2 + b*x + c = 0 , where x = e^theta. You can do it, don't give up. ;)
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    Sun vs Moon Tides: Understanding the Forces Behind Sea Tides

    Check this: http://oceanservice.noaa.gov/education/kits/tides/tides02_cause.html
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    Is there a limit for the solution of Navier Stokes equation?

    That is correct. You can find a very good and easy-to-read short essay about Kolmogorov theory here (PowerPoint file): http://www.bakker.org/dartmouth06/engs150/09-kolm.ppt
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    Is there a limit for the solution of Navier Stokes equation?

    As said above, Kolmogorov theory deals with turbulent flows at "sufficiently" high Reynolds numbers, whilst N-S equations can give either laminar-flow solutions or turbulent-flow solutions, depending on initial and boundary conditions. Think of a free uniform rectilinear flow, for example. If...
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    LaTeX Why are MathJax images not displaying on my webpage?

    Hello, I have a problem... I can't see the "Sigma" icon for creating LaTex code, even in advanced text mode... I've tried both IE and Chrome, but still no icon there. What am I doing wrong?
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    Maxiumum Incident power on solar cell ?

    1000 w/m2 is the standard value of irradiation, used for certification and comparison of PV cells - which is the case here, if I understood it well. For example, see this tech sheet of a Sharp 167 W module: http://www.abcsolar.com/pdf/sharp167.pdf - the bottom of the page 2, where it reads...
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    Why does a pneumatic motor run faster on helium than air?

    It can be explained in simple terms, imho, by considering a general equation: m = rho * V A time-derivative of this equation yields: dm/dt = rho * dV/dT or (since dV/dT = f * V0) dm/dt = f * rho * V0 where: dm/dt = mass flow of the gas V0 = motor displacement f = frequency of rotation...
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    Maxiumum Incident power on solar cell ?

    The power of sunlight at the ground level, when all the (mean) atmospheric dissipations and reflections have been detracted, is very close to 1000 W/m2 (outside the atmosphere it's value is 1367 W/m2 at the mean distance Sun-Earth). 1000 W/m2 is also the standard reference value used for...
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    Existence Without Mankind: Forum Discussion

    All in all, I cannot demonstrate my point of view, and you cannot do it with yours. And we could go on with this for the next couple of years, I think (btw: yes - I think therefore I observe, scupydog). I agree with scupydog, this pub is closing and maybe it's time to go home. Anyone for a...
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