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1. Please indicate which equations of theoretical aerodynamics (more precisely, fluid dynamics) have been refuted over time? The physical and mathematical basis is mostly just being extended. Yes, the empirical approach is still very common - not everything can be simulated, wind tunnel experiments are extremely important. But very often a calculation is sufficient for an accurate estimation of the parameters of a phenomenon.The equations are not a constant they are based on what is known about what is available, but material science is evolving too.
How long would it take to develop the F-35 using a purely empirical approach for aerodynamic optimization nowadays?If you gave all the plans for an F35 to Wilbur and Orville Wright in 1903 they would be impressed but they couldnt build one, and probably couldnt get one built in their lifetimes.
Really? If that were true, how do you know the weight of the aircraft or the strength of its wings and spars to know it could perform a 9G turn? Concorde famously changed in length when flying supersonic, such that the pilots on some last flights put their cap in a gap next to a bulkhead that isnt there when the plane is parked, without knowing the strength and elongation under load how do you allow for that in the design?1. Please indicate which equations of theoretical aerodynamics (more precisely, fluid dynamics) have been refuted over time? The physical and mathematical basis is mostly just being extended. Yes, the empirical approach is still very common - not everything can be simulated, wind tunnel experiments are extremely important. But very often a calculation is sufficient for an accurate estimation of the parameters of a phenomenon.
2. Materials science is poorly related to aerodynamics; in this thread we only consider the contribution of the latter.
How long would it take to develop the F-35 using a purely empirical approach for aerodynamic optimization nowadays?
Really. None of the above has anything to do with aerodynamics (fluid mechanics). It's either dynamics (pure mechanics) or mechanics of materials.Really? If that were true, how do you know the weight of the aircraft or the strength of its wings and spars to know it could perform a 9G turn?
Aerodynamics ... is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing.[1] It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics, and is an important domain of study in aeronautics.
The discussion is more around the definition of " aerodynamicist". For some people - including me - it is a physicist, a researcher who develops a scientific explanation of a phenomenon. For others, it is an engineer responsible for optimizing the aerodynamic properties of an object (aircraft, blower, etc.) using ready-made approaches developed by researchers.Not sure what this thread is about really; a few examples have been cited, yet discussion veers off every time it gets to specific individuals.
Thanks, so aerodynamics is nothing to do with designing aircraft, glad we sorted that one out.Really. None of the above has anything to do with aerodynamics (fluid mechanics). It's either dynamics (pure mechanics) or mechanics of materials.
Erroneous logic. Aerodynamics (equations, methods) is used to design airplanes, but does not mean design itself. Simply check out a textbook on aerodynamics (fluid mechanics).Thanks, so aerodynamics is nothing to do with designing aircraft, glad we sorted that one out.
Thanks for that clarification, now please clarify what an aerodynamicist does?Erroneous logic. Aerodynamics (equations, methods) is used to design airplanes, but does not mean design itself. Simply check out a textbook on aerodynamics (fluid mechanics).
An aerodynamicist deals with the description of the phenomena arising in moving fluids as well as during the motion of a body through a fluid. He predicts in particular pressure, temperature and velocity distributions in a fluid as well as forces and moments generated on a body moving through a fluid. "Prediction" means, here, the development of computational methods that can be described by mathematical equations. Aerodynamics textbooks for engineers often include a section on flight mechanics, which is not a section of aerodynamics but utilizes methods of applied aerodynamics.Thanks for that clarification, now please clarify what an aerodynamicist does?
I didnt ask for names I asked what they did, if not researching the theoretical answers to real world issues?Known aerodynamicists (researchers): Nikolay Zhukovsky (a founder of the modern aerodynamics), Ludwig Prandtl, Theodore von Karman, Adolf Buseman, Sergey Chaplygin, Hans Liepmann, Hermann Glauert, Mstislav Keldysh, ...
Ok, I agree, "applied aerodynamicists", however "not much of an engineer".Stanley Hooker...
The Wrights, Beverley Shenstone, Kelly Johnson, etc are applied aerodynamicists aka engineers.
He just followed the advice on thickness-chord ratio without critical analysis of the experimental conditions. However, critical analysis of the wind tunnel experiment was (probably still is) extremely difficult, so Camm simply lacked intuition.Sidney Camm was applied aerodynamicist - he took the data from the RAE wind tunnel and applied it to the design of his aircraft.
1. That wasn't an answer to you. I just listed the most important researchers in the field of theoretical aerodynamics.I didnt ask for names I asked what they did, if not researching the theoretical answers to real world issues?
Exactly, even when I was studying pure and applied mathematics I was given real wold examples and problems to solve. Discussing structures the size of the moon or ones made from materials of infinite strength and zero weight is a pointless activity.1. That wasn't an answer to you. I just listed the most important researchers in the field of theoretical aerodynamics.
2. Without exception, all theorists - even pure mathematicians - are engaged in the study of what is supposed to answer to "real world issues".
Tell me that the advice wasnt based on something in theory that turned out to be wrong? The laws are cast in stone and irrefutable arent they? Or is it like every other science, the rules are right until proved wrong by another rule?Ok, I agree, "applied aerodynamicists", however "not much of an engineer".
He just followed the advice on thickness-chord ratio without critical analysis of the experimental conditions. However, critical analysis of the wind tunnel experiment was (probably still is) extremely difficult, so Camm simply lacked intuition.
You just have a limited view of real world issues and don't see all the interrelationships between theory and practice. Any theory operates with abstractions, and sometimes it is extremely useful to consider the limiting cases first.Discussing structures the size of the moon or ones made from materials of infinite strength and zero weight is a pointless activity.
The advice was based on empirical wind tunnel data, not theory. But the experimental data was flawed because the effect of turbulence was not taken into account.Tell me that the advice wasnt based on something in theory that turned out to be wrong?
I have already asked for examples of theoretical aerodynamics equations that have been rejected subsequently.The laws are cast in stone and irrefutable arent they? Or is it like every other science, the rules are right until proved wrong by another rule?