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Bignose

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Everything posted by Bignose

  1. But, if you start from a wrong place, e.g. "the skin friction drag coefficient is defined as τ/q", then re-writing it doesn't matter. Because the statement in quotes isn't justified in the first place. What you've written here is NOT the definition used by, well, everyone else. THAT's what I want you to justify. THAT's what I want to see derived from first principles or the Navier Stokes equations. I've been asking! You haven't been answering! Once again, you decide not to address the large fundamental flaws, and nitpick on word choice! (Which, by the way, if you're going to nitpick on word choice, you probably need to make sure your words are right. It is Navier Stokes equations, not 'navies stokes'. It is named after two famous researchers, so it would be respectful to capitalize and spell their names correctly.) What am I supposed to think about this!?!? I'm at the point where I just want to give up because you seem very unresponsive to the questions I ask. But, I also want to help make sure you understand what I see as major issues with what you've posted to date, so I'm still on here -- but losing hope and interest fast.
  2. You keep using that word 'rational', though I do not think you know what it means. Again, I have zero problem with your belief, and I think many people share it with you. But, I don't describe it as rational. Because it isn't. It is a faith, there is no rationality behind it. So long as you accept it as a faith, then I don't think that anyone would have a serious problem with it. But, you can't invoke the word rational and bring in its implicit claims of strong, unbiased evidence and support with it. Because your belief just doesn't have that. It isn't 'rational' per the definition of the word 'rational'.
  3. I don't get this reply at all. Are you trying to imply that there isn't any theoretical physics in astronomy?
  4. Well then, that's wrong, because friction drag is already defined. See Leal or others. Friction drag does not include pressure in any way shape or form. You haven't 'proven' anything. You just set one thing equal to another, without any given rhyme or reason. And especially without support from the knowledge we have of fluid mechanics today, because your definition is at odds with the very commonly used defintion today. Fine. Quibble over a small language inaccuracy. (You do realize that quotient and product are tightly related, right? I was only trying to make it clear that it wasn't a sum as it is commonly represented.) Arguing on this is like arranging the silverware on the Titanic, but whatever. See, you're all over the map here again. You gave an equation for Cf. I take Cf to be the skin friction coefficient. But you set it equal to some equation that has a large chunk of the skin friction itself in it. NOT the coefficient. You seem to be mixing the drag coefficients and the drag itself. You must be extremely careful in being very explicit about what you mean. On top that the equation for skin friction coefficient or not has a pressure term, which, by definition, has nothing to do with the friction drag. No, you don't have proofs. You just assume forms for terms. That is not proof. If you want to talk proof, you would derive the forms for these equations directly from the Navier Stokes equations. Just like they do -- and I'm sorry I sound like a broken mp3 player here -- in the fluid mechanics texts. I believe you can log on to Amazon.com as well as I can. No, I don't understand it because it seems very haphazard and flung together without any substantial substance behind it. I understand the current fluid mechanics pretty well. Your hypothesis has a long way to go. Lastly, in accordance with silverware straightening on the Titanic, it cracks me up that you didn't bother to address any of the real issues I posted. Namely, the fact that using the shear stress at the wall for your calculation is troublesome because that is not very easily known. And that you still have posted very, very little supporting evidence -- and what you have posted is suspect to me at least. But, no let's keep arguing over product v. quotients, and your supposed proofs. In my mind, this is just more evidence of the lack of your background in this area, because I don't think you can recognize what the really important issues at hand are. That is, you think it is more important to correct quotient v. product rather than address the serious definitions that are at odds with the well verified fluids knowledge we have today. My point is, if you aren't going to bother using your calculations to compare to experimentally reported values, then what is the point? I don't get what satisfaction you get from them slapping together some functional forms and calling it a day. I'll give you one thing -- you are ahead of the vast majority of posters with a new 'idea' in that you are actually doing math. But, you haven't demonstrated in the least the value of that mathematics. No derivation it comes from first principles, no source given at all, and no demonstration that math actually makes useful predictions. So I guess -- again -- I don't have a lot of interest because you just aren't saying anything meaningful, and you don't seem to take my criticisms seriously.
  5. Rational would imply based upon strong objective evidence, to which the answer of this question would be no. As above, if you want to know what is rational based on the knowledge we have to date, you probably ought to start learning more about sleeping, neurology, and dreams. There is obviously more to learn than what we know today, but what we know today doesn't rationally support your statement above. Now, if your faith in that statement brings your inner peace and helps you live a moral, happy, and good life, then have it my friend. Just don't look for science to support it based on rationality.
  6. The Navier-Stokes equations if it is a Newtonian fluid. Your problem here isn't even all that uncommon -- it is the basis of why centrifugal pumps work. Any good undergraduate fluid mechanics text or class should discuss the workings of a centrifugal pump in detail.
  7. Thanks to whomever is giving me downvotes... stay classy out there. So... you're going to set the portion of the drag coefficient due to friction equal to the exact value of the viscous stresses at the surface. AND include something about some undefined pressure. I have no idea why you are just clumping these together willy nilly. Total drag is usually the sum of the friction drag and the form drag (that due to the pressure change). You're going to have to demonstrate that this product makes sense. Also, the drag coefficient, CD, is the dimensionless drag per unit length of a 2-D body (per unit area of a 3-D body). CD = (drag)/(denisty*characteristic velocity^2 * characteristic length). drag = friction drag + form drag friction drag is defined to be the shear stress at the wall, or viscosity*velocity gradient normal to the wall for a Newtonian fluid... on other words, what you set your coefficient to. which doesn't make sense. Furthermore, it doesn't really help to define your coefficient that way, since usually it is not very easy to know what the shear stress at a boundary is. That's why drag coefficients are measured in the first place... to get around the difficulties in calculating the shear stress at the wall. BTW, a lot of what I just wrote can be found in Leal's text referenced above. Had you read it, or maybe any of the other texts I posted, you would have know this. My recommendation would be to quit just flinging things around that you do not appear to have a good understanding of in the hopes of getting something to stick, and actually start on learning what we know today. At the very least, you need to know what is published today so that you can demonstrate that your idea is actually better... something you haven't done at all so far, BTW. Fluid mechanics has a lot of unknowns out there still, it is a very active area of research, but there are a heck of a lot of things we do know fairly well. And drag is one of those things. I am not saying that there isn't a lot more to learn about drag, because there is; but, what you're doing here conflicts with a great deal of the very well established knowledge we have so far. And you've provided zero evidence comparing your idea to what is known, and zero evidence showing us your idea is better. Either start providing that evidence, or this thread really ought to be closed. And please do yourself a favor and start working on understanding what we know today. I'll even go so far as to offer to answer questions about the texts I referenced above, when I have time... I have all of them, and have studied all of them in depth.
  8. Seriously? We're supposed to discuss based on a single equation? Without the terms used in it defined? Why don't you show us... plot the predictions made by the current best dark matter theories, the predictions made by your equation there, and the current best experimental values. That would go quite a way towards helping to figure what is 'righter' [sic].... 'more correct'.
  9. Bull****. Little to no lift for airfoil?!?! You're just making this up now, I won't be back until you say something meaningfull.
  10. from what you described the other effects as, I don't see how they can be described as 'slight'. And it sure is convenient that a=b, isn't it? Why would you use two different variables in the first place if a = b? This hand-waving dismissing of my concerns is getting quite annoying and is a major reason I kind of stopped writing back the first time...
  11. Yeah, I'm with you. It is a significant reason I still post as much as I do in Speculations... to try to give a different point of view and not just let OPs run unfettered.
  12. This is very true, and the toughest pill for most of us to swallow. Speaking for myself, I am ever the optimist that maybe, just maybe, with just the right words, that we might just get them to step back and actually understand. My estimate for the success rate on this is probably 1-2%. Anything anyone has as a suggestion to increase that significantly would be greatly appreciated.
  13. I stated he existed. That's the level of evidence you provided. You simply stated that there are 4 days. I think my 'evidence' is just as good as yours. How is my evidence really different?
  14. Do you really want to play this game? Ok, I will. You've yet to provide any reason not to believe in my invisible pet dinosaur. Scruffy's feelings were really hurt when you implied he wasn't real. If you don't believe in Scruffy, and not posting any real reason not to, explain why your story is more believable than mine.
  15. The same rules still apply. Clear cut, objective, statistically significant evidence.
  16. It is not up to science to refute every single notion that someone should happen to come up with. Science works in that when someone has a notion and wants others to believe in that notion, they provide objective, clear cut, statistically significant evidence to support their notion. A trivial example: If I told you that I kept an invisible pet dinosaur in my garage, are you really going to believe that until it is refuted? Science would demand that I provide overwhelming evidence of Scruffy until anyone should believe me.
  17. Fine. I'm going to reply to this, though I am loothe to actually need to do it. Sometimes, not all of science is glamour and exciting. Sometimes, it is re-transcribing plotted data into another format. Sometimes, that means printing out a graph at as high a resolution as possible and using a ruler and re-typing all the x & y points. That way, you can plot someone else's graph on the same graph as your own. So, now that that is out of the way, any chance you'll address some of the other criticisms I've had? Like the one where you just changed the functional form for no apparent reason (the rotation may explain why you can go from sine to cosine, but it does NOT explain why you can change from the sum of two different cosines to a single sine), or why all the other terms but Cf go to zero on the lone data set you've considered despite the functional forms you've posted showing that there is no way that that should happen?
  18. but as near as we can tell, space alone doesn't have the necessary attributes. That is, space itself doesn't seem to exert and experience the gravitational forces needed to prevent galaxies from flying apart. And, because we don't see galaxies flying apart and we don't see enough visible (or light) matter in those galaxies for all the gravity that ought to be there, we figure there is something we're not seeing keeping the galaxies together. As alluded to above, we can actually make maps of where dark matter is most likely to be. http://www.scientificamerican.com/article.cfm?id=biggest-map-yet-of-universes Dark matter isn't just space because space doesn't have higher and lower densities like that map. But, it certainly has a significant number of unanswered questions at the moment.
  19. I don't believe this for a second. The literature is full of published drag correlations. I have serious doubts that you've even bothered to look. It's your idea, no one else should be expected to do your work for you. Go and start with a fluid mechanics text, and start going through the references the book will have. I did promise you some references a few posts back, so let me fulfill that promise now: I'd recommend Fox and McDonald's Introduction to Fluid Mechanics. This books is an excellent intro, and will give you a good working knowledge of how fluid mechanics is typically used. Then, you need to tackle a graduate level text that will do a more in depth dive into the properties of the Navier-Stokes equations. I'd recommend L. Gary Leal's Laminar Flow and Convective Processes. Slattery's Advanced Transport Phenomena is a good supplement. Then, you need to dive deeper into the fluid flow at a surface. Schlichting's Boundary Layer Theory is the gold standard in this area of research. You also need a good understanding of turbulence. P. A. Davidson's Turbulence: An Introduction for Scientists and Engineers looks good; Davidson has been in the field for a very long time. Another good one is Pope's Turbulent Flows. Lastly, a delve into multiphase flow would help as well. A lot of the drag correlations have been measured in order to make the multiphase flow predictions more accurate. Crowe et al.'s Multiphase Flow with Droplets and Particles is good. Fan and Zhu's Principles of Gas-Solids Flows is also highly recommended as is Rhodes' Introduction To Particle Technology. From these texts, you will find an extraordinary wealth of references which describe the papers doing the experiments that measure drag. Especially, those multiphase flows. So, to recap: I don't believe your quoted word for second, because the references I posts about is literally 1/100th of all the good texts on fluid mechanics. Maybe 1/500th of all the poor texts. But even the poor texts discuss drag and will have citations you can look up to find more. If you are serious about this endeavor, you need to be putting in the time with the advanced texts. Though I guess really, the first point is that you need to learn how to make a graph. That is a really basic skill that cannot be ignored.
  20. I think the greatest human invention is farming. To use the criteria above, things would grow from seeds whether human were around or not. But the act of choosing what to plant, to cultivate the plants that reliably gave us the best produce, that's the invention in my mind. I also think you can reasonably successfully farm without mathematics. Plant stuff when it is no longer cold. Harvest stuff when it is done growing. Mathematics makes agriculture more scientific for sure. But I think it can be done pretty successfully without math.
  21. ... and yet, I can buy one if I want to: http://www.kleinbottle.com/
  22. Here's another flaw. The sun is also a very prodigious source of neutrinos, yet the earth and all the planets seem to be attracted to it instead of repelled.
  23. I stopped reading right here. Because, it is not up to any of us to disprove your idea. It is up to you to provide sufficient objective evidence that your idea matches evidence. Science does not just accept any idea until disproven. As a farcical example, you're not going to believe that I keep an invisible pet dinosaur in my garage until you disprove it, are you? This does make science conservative. But it has worked exceptionally well to date. Now, as for evidence. Answer swansont's question about the hydrogen spectrum. Show us that your idea makes some kind of useful prediction that agrees with known measurements.
  24. You're comparing apples to T-24 Soviet tanks. Sure, beauty may have been a motivator for looking into super symmetry. But ultimately, if the predictions coming from super symmetry is wrong, it won't matter a whit how aesthetically pleasing it is. It will be rightly rejected. THAT's the problem with the OP here. OP is letting beauty trump everything else, which is just nonsense scientifically.
  25. Sure. But did you miss the last sentence you quoted of mine there? The universe is under no obligation to be aesthetically pleasing to us. It is fine if an idea is beautiful AND turns out to be right. But it isn't scientifically useful to have a beautiful idea that is wrong. It can be nice to look at, but if its scientifically unusable, science rightly rejects it. Because scientifically, the idea that makes the best predictions wins, whether that idea is beautiful, ugly, or anything in between. So the OP's idea of overtones and 7 pure colors and all that is pretty. But it just doesn't fit the facts in any way shape or form. So, it really has no value scientifically. I don't know what more needs to be said. No amount of wishing the beautiful idea was true will change the facts, so why bother?
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