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I'm working on my PhD in aerospace engineering, specializing in computational turbulent combustion. My focus is primarily on massively parallel algorithms and computational methods for solving fluid and structural mechanics problems. Primary work is done in Fortran (90, 95, and 2003) but recent work has me branching into python, C and C++.

I'm also interested in international affairs and law.

Also interested in applying computational techniques to sports, in particular cycling aerodynamics and performance optimization. Particular emphasis on track cycling and time trialing.


20h
comment If a body is floating in a static fluid, then the volume of the displaced fluid equal to the volume of the inmerse part of the object (proof)
Ever take a bath?
Sep
18
comment What is “full clutching flow” in fluid-dynamics with regards venturi design?
A quick google search turns up... only this question. Without a reference, we can't really help.
Sep
16
awarded  Nice Answer
Sep
16
comment What is a Physically Accurate Explanation for the Kutta Condition?
The images you show are at large angle of attack and show separation, which is why there is no rear stagnation point.
Sep
16
comment What is a Physically Accurate Explanation for the Kutta Condition?
Can you give a citation that says there is no stagnation point at the rear point in low Re flow? Stokes flow over a cylinder and over airfoils both have rear stagnation points. In fact, the solutions to those flows look identical to the potential flow solutions, confusing many people about why the potential solutions don't hold at low Re.
Sep
16
comment What is a Physically Accurate Explanation for the Kutta Condition?
@BrysonS. If the flow remains attached, which for all this to be valid we assume it is, then I can't think of a more physical explanation... it just seems intuitive to me at this point. If the velocity is zero at the front, and zero along the body, and the body is a streamline, then it must also be zero at the trailing edge where the two zero streamlines meet. I'll dig through some other authors for other explanations, but I'm having a tough time seeing where the confusion lies since it seems intuitive to me... but I'll try!
Sep
16
comment What is a Physically Accurate Explanation for the Kutta Condition?
Also -- and this is just being pedantic because we can be once in awhile -- you state that no man-made object can be perfectly sharp (zero radius of curvature). And while true, we are capable of creating knife edges that get down to nanometers in thickness at the very edge. Since this is well below the mean-free-path of air at atmospheric conditions, this is effectively zero radius of curvature over the length scales of the flow.
Sep
16
comment What is a Physically Accurate Explanation for the Kutta Condition?
@BrysonS. I added the explanation from my other answer to a similar (but not duplicate) question... I guess it just works out that the answers are duplicates, even when the question isn't. It provides some math explanation but really it's more of a physical explanation. Unfortunately, the real problem is so complicated that it's difficult to boil the math down to an analytical problem -- numerical solutions are about all you can do.
Sep
16
revised What is a Physically Accurate Explanation for the Kutta Condition?
added 1537 characters in body
Sep
16
comment What is a Physically Accurate Explanation for the Kutta Condition?
@BrysonS. Remember that they are solving the potential equations over a simplified model of the airfoil. In the simplified problem, the trailing edge is infinitely sharp. It is because the equations to generate it will generate an infinitely sharp edge. There is nothing bogus or baseless about that either. I think part of your confusion is connecting the mathematical approximation to real life. They are two distinct things, and if we're really lucky, the former will describe the latter pretty well.
Sep
16
comment What is a Physically Accurate Explanation for the Kutta Condition?
I'd like to point out that your examples where "we know the KC is not upheld for very low Reynolds numbers" is not a proof that the KC is wrong or baseless. Reynolds number is the ratio of inertial to viscous forces, so very low Re means viscous forces dominate. Meanwhile, the Kutta condition is something we impose in potential flow equations, which assume infinitely large Re (negligible viscosity). So of course it doesn't hold, it's not supposed to. The equations that use it aren't valid.
Sep
16
comment What is a Physically Accurate Explanation for the Kutta Condition?
@BrysonS. No, not at all. In fact, I think it explains it quite well. The only way to get a solution to the potential equations that has the flow leaving the trailing edge smoothly (like what is observed in physical situations) is if the Kutta condition is imposed. What in there do you see as baseless or misleading?
Sep
16
answered What is a Physically Accurate Explanation for the Kutta Condition?
Sep
11
comment Feeling the Breeze
Why do you consider those two reasons far fetched? I mean, both of those things happen and are totally consistent with what fluid dynamics predict -- so your intuition is right, but why do you feel it's not?
Sep
5
comment Thought experiment: Tethered galaxies - to the extreme
Just so I think I understand what you're asking -- you want to know if matter (the rope) expands along with the metric expansion of space if it were to stretch across the universe? It just needs to be clear because your rope is already completely impossible, so asking if it would "break" doesn't have an answer -- it's a magical rope, we can make it do whatever we want.
Aug
30
comment Why do we need the material derivative?
Depending on how you are solving the equations of motion, one form is preferred over the other. If you model the flow as discrete particles (Lagrangian formulation) then you solve the material derivative (and it's a coupled set of ODE's in time) whereas if you solve on a fixed domain (Eulerian formulation), you solve the second form. Some problems are better in one than the other.
Aug
30
comment Why do I always hear remote train horn at night?
What country do you live in? There may be a non-physics answer here -- some places don't require horns for level crossings during the day but do at night when visibility is lower. So the horns just may not be sounding or may not sound as loud during the day when they aren't needed.
Aug
29
comment Best Research Documentation Habit for Computational Physics Research
Makefile? CMake is so much better...
Aug
28
comment Norsk Hydro and heavy water - what was the perceived threat?
@akrasia The wikipedia article seems to indicate that graphite wasn't viable at the time and that both the French and Germans knew this, and knew that heavy water was needed. More details than that, and we'll have to hop over to history.SE to get answers.
Aug
28
comment “Rocket in a box” thought experiment
Try to think about where the center of mass of the system is at all times throughout each case and you should be able to visualize what happens. A rocket just converts a solid or liquid to a gas, but the total mass of the original fuel and of the products is the same.