Questions tagged [drag]
Aerodynamic drag is the fluid drag force that acts on any moving solid body in the direction of the fluid freestream flow. Part of the drag is the direct consequence of the wing generating lift.
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Downwash, Lift-Induced Drag and Wing Tip Vortices [closed]
I've been reading many of the answers that Peter Kämpf and
Jan Hudec have posted over the years. After many hours of reading the responses here, reading Anderson's Performance and Doug McLean's ...
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Does dynamic stability decrease with airspeed
Context: I am writing my thesis on the topic of satellite drag reduction by the means of near-specular surface scattering. The theme touches aerodynamics in some sense, but the physics are honestly ...
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What is the supersonic L/D of subsonic jetliner
Suppose you somehow managed to accelerate a typical jetliner oastbthe sound barrier and to whatever speed you wanted, climbing to keep lift constant. Is there any data on his the L/D evolves with Mach ...
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How does a thickening boundary layer create form drag?
Imagine a normal wing with flow over it, and to simplify things it's at 0 AoA. Drag is being made mainly because of form drag and skin friction drag. I'm not sure on this, but I don't think there ...
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wave drag: Lift coefficient in Korn's Equation
I have been using the Korn equation:
$$
M_c = \frac{0.95}{cos(\lambda)}-\frac{t/c}{cos(\lambda)^2}-\frac{C_L}{10cos(\lambda)^3}-\sqrt[3]{\frac{0.1}{80}}
$$
to estimate the critical mach number of a ...
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In a straight and level flight if thrust is equal to drag how is aircraft moving forward?
If two forces are equal and acting in opposite direction should not the object remain stationary.
Is there an excess thrust which actually pushes the aircraft forward ?
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Can there be interference drag in inviscid flow?
I understand that interference drag is the difference between the terms: the total drag of a configuration, and the sum of the individual drags of the components in the configuration. (It exists due ...
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How does the lift-to-drag ratio depend on absolute sizes?
A dependency is provided here
$$(L/D)_{\max} = \frac{1}{2} \sqrt{\frac{\pi \varepsilon ~ \mathrm{AR}}{C_{D,0}}}$$
AR significantly affects the outcome in this dependency. AR varies significantly among ...
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Range, Endurance and Fuel Cost Savings of an Aircraft
I have recently carried out CFD simulations on the A320 fuselage and modified its fuselage. I did this by matching the Reynold's number of the cruising altitude. The reference values were taken at ...
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Determining Sectional Drag Coefficient Using Propeller Geometry
Im trying to teach myself blade element theory for helicopters and propellers, but im getting quite confused.
Most of the papers and textbooks I read will reach an equation for differential thrust ...
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Is induced drag only created by wingtip vortices induced downwash?
In PHAK, I saw that There is two types of downwash
formed by airfoil shape that necessary(help?) to produce lift
formed by wingtip vortices
in phak 5-7 It said 'This induced downwash has nothing in ...
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In which position does Starship wings produce the most drag?
I was watching the video from a few years ago where SN15 did the flip manoeuvre and landing. The actuated fins (lower flaps) can help Starship to pitch while during its descent. However, I am ...
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Why does turbulence over a wing make drag?
Drag is the result of air ‘pushing’ the opposite direction of flight, if you want to think of it that way. The skin friction drag is made from the air trying to pull the wing opposite of the flight ...
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Why is a half-streamlined body less aerodynamic?
As seen here, a streamlined half body is less aerodynamic than a fully streamlined body. The half streamlined one has less surface area (kind of) and less frontal area. Why is its drag more?
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Minimum sink speed and maximum endurance speed
For a given airplane, are the minimum sink speed and maximum endurance speed the same?
Thankyou
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