User talk:Moink/archive160304

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Hi moink

good to hear from you. I've had a look at the wikibook and the fluid mechanics page. Thanks for your encouragement.

I've spent some considerable time pondering how to rejig the fluid mechanics pages. It is not at all obvious how best to do it... it's bad enough trying to organize a dead-tree book, but the natural hypertext crossreferencing available on wiki makes the task simultaneously harder and much easier.

Still, it's pretty clear to me that the fluid mechanics wikipedia page needs a radical overhaul. Your point about various equations being special cases of other eqautions is spot on.

How about this for a start.

(1) the distinctive properties of fluids and the Navier-Stokes Equations
(2) commonly-used simplifications of N-S:
(a) steady flow
(a) potential flow (not yet written but I'm working on it!)
(b) Euler equations
(c) N-S with constant: density, viscosity.

aside: is it worth considering things like the shallow layer equations, the Korteveg-deVries equations here? what do you think? these are special cases of the N-S equations but with some rather wide-ranging assumptions!


(3) commonly encountered (practical) fluid flows. General idea is to follow Van Dyke and structure from low Reynolds number flows to bigger ones (ie creeping flow to hypersonic flow) but this isn't such a hot idea if you subscribe to the notion (as I do) that all dimensionless numbers were created equal. Nevertheless, this is a sensible way to order fluid phenomena. I just started to write my list of examples (from continental drift to hypersonic flow) but realized that there are just too many. Perhaps we should take a leaf from the millisecond series and have a similar bunch of pages entitled something like Reynolds number 0.001 to Reynolds number 100000? what do you think? what are the naming conventions here? Each one could point to subentries (eg lavalamp or sunspots or whatever. This way we could create some structure.

(4) investigative techniques:

(4a) CFD (already covered)
(4b) lab work
(4c) field work (terrestrial/oceanographical)
(4d) astronomical
(5) history
(6) personalities.


This is arguably not a NPOV: I am unashamedly a theoretical scientist!

Maybe we ought to discuss on the discuss page of fluid mechanics? see you there!

Robinh 23:00, 1 Jan 2004 (UTC)

I think you might be exactly who I'm looking for to talk about the organization of the fluid dynamics pages. I'm trying to write aerodynamics (it's been a stub for a long time) and it's going really slowly. It's occuring to me that much of what I'm writing there really belongs in fluid mechanics (like the continuity assumption etc) but then aerodynamics would reduce to a simple "Aerodynamics is fluid mechanics applied to gases" and nothing else, which doesn't work for the importance of the topic. And I keep wanting to insert Bernoulli's equation, the Euler equations, the Navier-Stokes equations, even LaPlace's equation but of course they all have their own pages, so it would just be duplication. And yet nowhere do we have the fact that they are reductions of one another. Also, should I be making new pages for things like Prandtl's lifting-line theory or does it belong in aerodynamics? Anyway, let me know your thoughts, I've started a Wikipedia:WikiProject Fluid dynamics to get it going. moink 17:28, 27 Dec 2003 (UTC)

Hi moink, about the area of a sector of an ellipse, I used MATLAB to numerically verify the analytical expression I gave. Here is the code I used:

a = 2; % this is just the value I used
b = 5; % likewise

% set up variables
x = 0:0.01:a;
y = b*sqrt(1 - ((x/a).^2));
theta = acos(x(1:(end-1))/a);

% numerical integration
for i = 1:(length(x)-1)
area_numerical(i) = trapz(x(i:end),y(i:end));
end

% analytical formula
area_analytical = 0.5*a*b*(theta - cos(theta).*sin(theta));

%compare visually
plot(theta, area_numerical, '.-', theta, area_analytical, 'o-');

%compare numerically
max(abs(area_numerical - area_analytical))

Cheers, Cyan 19:01, 27 Feb 2004 (UTC)

I went back and did the polyarea thing too:

% x and y defined as above
x(end + 1) = 0; y(end + 1) = 0; % puts the origin into the polygon
theta = acos(x(1:(end-1))/a);

% numerical integration
for i = 1:(length(x) - 1)
area(i) = polyarea(x(i:end),y(i:end));
end

%visual comparison
plot(theta, area, '.-', theta, 0.5*a*b*theta,'o')

Cheers, Cyan 19:19, 27 Feb 2004 (UTC)

Well, the hard part is analytically integrating the equation for the ellipse, and the credit there belongs to the good folks at MathWorld. -- Cyan 20:42, 27 Feb 2004 (UTC)

Contents

Mixed vegetables vfd

Hi. On Dec 27, 2003 you added the vfd notice to Mixed vegetables. Since the page still exists, I assume the consensus was to keep the page? I cannot find the related discussion. Thanks. RedWolf 22:06, Feb 28, 2004 (UTC)

STS-85

Hey Moink, just wanted to give you a heads up on the links at the bottom of the page. You should link to STS-94 and STS-86 going forwards and backwards, not just xx (those are years) see STS-27 for the template Theon 18:29, Mar 4, 2004 (UTC)

Sorry

I must be in a bad mood today -- I apologized at the pump. Didn't mean to target you with my frustration: the VP seems to have a lot of people watching it, and yet too often (it seems) they dump questions on the reference desk, which I feel is ignored by far too many people here. But you're right, you do a very good job there, and I was speaking badly. I hope you will accept my apology, Jwrosenzweig 21:41, 4 Mar 2004 (UTC)

Koopsta Knicca

Your nomination of Koopsta Knicca was removed after one day. Is this your intent in light of the changes to it or did you still want it listed for the full 5 days? Thanks - Texture 19:30, 5 Mar 2004 (UTC)

Things are removed from VfD all the time when they get too long. Anthony DiPierro 22:12, 5 Mar 2004 (UTC)

The way I saw it moving everything to the talk page *was* the compromise. But as long as the discussion isn't separated from the votes, I'm fine with it. Anthony DiPierro 03:27, 6 Mar 2004 (UTC)

re: vfd discussion belongs on vfd except in extenuating circumstances

There are extenuating circumstances. VfD is 110kb! Angela. 14:06, Mar 6, 2004 (UTC)

Thank you for the advice on adding hyperlinks. I see also there is a link to R-parity...a suggestion perhaps? Also, would it be helpful and/or legal to link to relevent [Mathworld] sites? Ie with a See Also at the bottom of the page? Best regards! Pharotic 7:20, Mar 7, 2004 (UTC)

Hi, I replied at User talk:Angela#vfd belonging on vfd. Angela. 11:57, Mar 7, 2004 (UTC)

Contest

Well I'll bite.  :) Female/Canadian/Vancouver is my guess for today. fabiform | talk 20:05, 7 Mar 2004 (UTC)

I will guess male, American, Chicago. Adam Bishop 20:06, 7 Mar 2004 (UTC)

I'm going to guess male, originally from Canada, but now living in Boston. Angela. 20:13, Mar 7, 2004 (UTC)

Just a guess. You're a German man, living in the USA near Wichita (Kansas) Pfortuny 20:53, 7 Mar 2004 (UTC)

Female, Canadian, Boston/Cambridge, Massachusetts area. Maximus Rex, 21:24, 7 Mar 2004 (UTC)

I guessed as there is a link on what I assumed could be your website to a guide to Boston. Angela. 21:57, Mar 7, 2004 (UTC)

I thought moink.org must be yours. Is there more than one moink in Boston? :) Angela. 22:04, Mar 7, 2004 (UTC)

I based mine just on your contributions. Female because you've edited several female biogs and feminism things. And the rogue Vancouver because that was the first place you made an edit about.  :) Did you enjoy our guesses? fabiform | talk 22:00, 7 Mar 2004 (UTC)

I think all the maths and fluid dynamics put a lot of people on the wrong track re your gender. Plus, statistically, there are more male than female users I think, so it was a safe bet.  :) fabiform | talk 22:09, 7 Mar 2004 (UTC)

Hans Sachs

Hi Moink, You've put a vfd message to Hans Sachs, but i can't seem to find it on vfd in order to vote KEEP. Am i stupid or is somethin wrong with vfd? btw i like your context but now i must rewrite Hans Sachs instead of sifting through your old edits ;-)))))) Lady Tenar 21:29, 7 Mar 2004 (UTC)

The Contest

The location I determined from [1]. The Candian I guessed from Bjarni Tryggvason. The gender I was going to guess male (on the internet I guess I assume users are male unless otherwise indicated), however Angela had not been recognized as correct for her guess.

I will offer you a few choices for the article to improve. I couldn't find much on Friedrich Ernst Dorn, who is credited as discovering radon, on the internet. Another article that could use improvement is Jan Hendrik Schön. If you don't want to improve either of those, I won't be too offended. Maximus Rex, 22:06, 7 Mar 2004 (UTC)

Great improvements to Jan Hendrik Schön! I release you from any obligation to further improve it. I must say that enjoyed this little contest. Maximus Rex, 08:03, 8 Mar 2004 (UTC)

Jus ad bellum

A google search and some reading provided info on its usage and history. JimD 10:20, 2004 Mar 8 (UTC)

D. Williams

heres the answer to your question: STS-90 And the reason that you probably couldnt find him is that his name is spelled daffydd not daffyd ;-) Ive taken the liberty of pulling his profile and copying it to his wiki site. [[2]]Theon 00:38, Mar 9, 2004 (UTC)

Daffyd Williams

Thanks

Thanks for the words of kindness, moink (or should I call you Teresa? I believe that's the name you use on the mailing list, but I'm always in a quandary regarding username versus first name. 2/3 of the people here address me as Jwros and a few others as James....I guess none of us know) -- I appreciate it very much, and am glad to know I can do something worthwhile here on occasion. Having just now seen your userpage, I think I should mention that I was a student at Simon Fraser University for 2 years, so I know Burnaby moderately well should you ever get homesick for it and want to reminisce. :-) What part of town did you reside in? Anyway, I came here to thank you for being encouraging, and I do want to emphasize that you have risen very much on my "radar of trust" in the last 6 weeks or so -- I'm very glad to see your contributions here, and hope you are sticking around for the long haul! Happy editing, Jwrosenzweig 17:19, 15 Mar 2004 (UTC)

By the way, I've nominated you for adminship, which I hope the community supports (I can't imagine they wouldn't) and you will accept (I don't envision you will, but it's a possibility). Sometime in the next few days, please leave a note at RfA announcing your acceptance or rejection of my nomination. Thanks so much for your good work here! Jwrosenzweig 17:29, 15 Mar 2004 (UTC)
Well, moink, I guess I'd say that for talking directly to me, James is a good choice for typing ease. For referring to me in large fora (the pump, mailing lists, etc.), I think my user name or some approximation of it might be better, as we have (at the very least) James F. and JamesDay here. Always tough to know. And BCIT, hmmm, seems to me that was on a bus route of mine, perhaps between SFU and Metrotowne? I'll have to think on it. Wish I'd known BCIT better -- I'd write the article. :) Jwrosenzweig 17:37, 15 Mar 2004 (UTC)