Questions tagged [vortex]
Questions about vortices (channels of swirling air) generated by aircraft, which can be either desirable or undesirable.
27 questions
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Flow separation in inviscid flow
I watched this video about CFD (
) where flow was assumed to be incompressible and inviscid, but how can vorticies occur behind the ball at the start of the video, shouldn'...
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How does a shear layer make vortices?
How does a shear layer make vortices? If you have 2 streams of air that are moving at different speeds or opposite directions right beside each other, how would that make a vortex? What causes the ...
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What causes the oscillation in vortex shedding?
When studying this video, I was wondering what actually causes the oscillation? Any source online that I found said that it was from oscillating low pressure zones, but what causes that?
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Why do flat wings create a vortex/vortices?
I've been researching this for the past ~45 minutes, and I still can't find a solid answer. Why do flat wings create a vortex/vortices? In this answer, it says that the detached flow will create a ...
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Do 2 vortices next to each other have any attracting force?
Do 2 vortices next to each other have any attracting force?
Say you have 2 tip vortex sized vortices next to each other. Will they have any sort of attracting force toward each other? If they do, why ...
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How do 2 vortices (or more) combine when they are near each other?
If you have 2 vortices rotating the same direction, how will they interact with each other? For example, if you have 2 tip vortex sized vortices close to each other and rotating the same direction, ...
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Does the bending air on a wing create one or multiple vortices?
As explained in the first paragraph of this answer, air will bend inwards on the top of the wing, and outwards on the bottom of the wing. This creates an inward flow component on the top of the wing ...
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Where are the vortices from the trailing edge on the wing of a plane? [duplicate]
I always knew planes made these vortices when going through clouds/smoke, but I thought they were just tip vortices. Looking further into it, they are way too big to be tip vortices, so they had to be ...
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Can wingtip vortices formed around an unswept wing produce vortex lift?
Vortex lift is a kind of aerodynamic lift force due to vortices formed along the leading edge of highly-swept (usually 60 degrees of swept angle or higher) wings at high angles of attack. The "...
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Do trailing edge vortices exist in reality? [duplicate]
Please don't talk about wing tip vortices and leading edge vortices(vortex lift)
Is it possible to see trailing edge vortices in real life, do they exist in reality?
How looks air in wake between ...
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Why does the leading edge vortex accelerate the flow downward?
I know leading edge vortices over delta wings make more lift. I understood that the core of the vortex sheet is low, so there is suction flow that makes lift. But, I can't understand how a leading ...
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Can gliders and single-engine planes have vortices?
I read,
A third physical explanation of the source of induced drag is that the
wing tip vortices contain a certain amount of rotational kinetic energy. This
energy has to come from somewhere; indeed, ...
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How do wing tip vortices that interact with the wing surface affect drag?
Often people say vortices are behind the wing so they cannot produce drag, I am not interested in those vortices behind the wing....
I am interested how wing tip vortices which interact with the ...
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Velocity induced by a straight vortex filament
Consider a straight vortex filament as shown below. At each point, there's a point vortex of strength $\it T$. Consider that a point $P$ is there on the outermost circle of flow induced by the vortex ...
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How does vorticity change the lift coefficient of an airfoil?
For airfoils in unsteady motion, the lift coefficient oscillates and the wake is characterized by vortex shedding.
How does vortex shedding affect the lift coefficient for an airfoil?
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What is the role of a bound vortex?
From what I know the term bound vortex comes from potential flow theory and is a part of circulation around a wing.
Does it mean the same as circulation or lift?
Is it a cause of generating lift over ...
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Why does the Biot-Savart law give the induced velocity of a infinitesimal segment of a vortex filament at point P?
My question is about the proof of how the Biot-Savart law can be used for vortex filaments. This is what I have in my textbook:
However, I'm not certain how it was derived - I understand that the ...
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Are there any aircraft with retractable vortex generators?
From this answer, “Of course, these also add drag, even when the wing is not stalling, so they are only added where needed”. Are there any aircraft that have vortex generators that are retractable so ...
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What is the reason for circulation of air around an airfoil? Based upon the circulation of air, why are airfoils shaped the way they are? [duplicate]
Foreword: I am an Aerospace Engineering student and next year is my third and final year, starting September 2019.
I was taught approximately 2 semesters ago that the correct theory of lift is that ...
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How do the vortices of a fixed wing and horizontal stabilizer interact? [duplicate]
What interaction of vortices between the fixed wing and horizontal stabilizer?
How do the vortices affect the flow of the horizontal stabilizer upon leaving the wing?
when will the downwash effort ...
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Does an aircraft with higher aspect ratio wings produce more wingtip vortices in a turn than one with lower aspect ratio wings?
The Ta-152H was well-known for having very high-aspect ratio wings: 8.94, if I'm not mistaken. Now, compare this to the P-51 which had, if I'm not mistaken, an aspect ratio of 5.86. Does this mean ...
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What's the shape and place of the tip vortex in a propeller, depending on propeller sense of turning?
If the propeller vortex is placed and has changing features depending on the propeller sense of turning, both in traction and pusher configuration, knowing about this may have an interest for the ...
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How and why do wake vortices come together to form two tip vortices?
Wake vortices are created all along the wingspan but, the vortices come together to form two tip vortices. How exacly does this happen and why does it? I know that wake vortices push air to the side. ...
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How to derive the Vortex line segment parallel to a plane using the Biot-Savart law?
I am trying to understand what is shown in this book (Applied hydro and aeromechanics), page 187
The velocity induced at a given point on a parallel plane by a vortex segment of length $b$, and ...
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What aspect ratio is best for Wind Tunnel Testing an aerofoil with Small Additives? [closed]
Vortex generators will be 3D printed on a panel, which is then to be slotted onto a foam aerofoil to be tested in the wind tunnel for performance and flow physics.
What I want to know is which aspect ...
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Can these vortices be dangerous?
There is a question related to this one right here but I'm more interested in the danger of those vortices. Are they very dangerous to cause a wake turbulence for the aircraft that comes behind this? ...
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What is the working principle of gravel kits?
In this answer gravel kits are mentioned. I then looked at the wikipedia page and I noticed that they are quite different from what I was expecting:
I was expecting some kind of "shield", plate or ...
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