Questions tagged [airfoil]
The 2D shape of a section of aircraft wing.
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Can a 747 airfoil be scaled down for smaller jet planes?
At the loss of its acrobatic ability, could an airfoil similar to the 747 be downsized to allow a small jet to climb higher and extend its range?
This plane with its wing profile is highly acrobatic, ...
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Are Foward Swept Wings for a Rear Propeller Airplane Feasible?
Would going with a forward swept wing design, with the same cord and length of the "A Wing", bring more air the the propeller and tail to increase range, power, or stability?
Consider the ...
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Is there a formula for calculating drag coefficient based on the 4 digit NACA airfoil?
Are there any existing formulas that can be used, or maybe some methods to derive an equation that can calculate the drag coefficient based on the NACA airfoil?
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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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Is any airfoil design free to be used? Are they proprietary? Are NACA's airfoils proprietary? [duplicate]
Here I found database of various airfoils, including NACA's airfoil. Some of those airfoils seems like belong to particular company seen from their name, like belong to Boeing, Lockheed, RAF, Sikorsky,...
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Is there a formula for calculating lift coefficient based on the NACA airfoil?
Are there any formulas that can be used to calculate this?
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meanings of the numbers in the airfoil NACA 65(12)-10, where to find and plot
I am trying to plot an airfoil named NACA 65(12)-10 in javafoil. I found it in a few research articles. However, I am not sure from what series the airfoil is from. I tried looking it up on ...
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What airfoil can be used in making a turbofan engine fan blade? [duplicate]
The thing is, I am trying to make turbofan blades in Solidworks for a possible undergraduate thesis. I would like to know if there is any airfoil from the NACA series or anything plausible for this ...
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What airfoil family does turbofan's fan blades use?
The thing is, I am trying to make turbofan blades in Solidworks for a possible undergraduate thesis.
I want to know if there is any airfoil from the NACA series or any airfoil families plausible for ...
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What are the type of airfoils being used in Russian fighter?
I've tried to search for airfoils that are being used for Russian fighters such as Su 27/ 30/ 35 and MiG 29 on the internet, but it seems that this type of information is classified. What type of ...
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Flying wing airfoil
What would be let say some of appropriate airfoils for flying wing RC model ? Wingspan arround 1200mm and speed arround 700 km/h.
Maybe MH64 or so ?
Thank you,
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Wind turbine airfoil on low Reynolds number aircraft
I read that the criteria considered when designing a wind turbine airfoil are slightly different to the ones when designing an airfoil for an aircraft. I was wondering, for a low Reynolds number ...
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How does camber location (xf/c) affect Cl max and stall angle of an airfoil [duplicate]
I'm trying to compare 4-digit airfoil and 5-digit airfoil about the effect of camber location towards Cl max and stall angle.
Is it correct if i assume the higher the camber location value the Cl max ...
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Where can I find a list of higher lift laminar airfoils?
Does anyone have a list of laminar-flow airfoils (so I can compare them) with a Cl at 0°AoA of preferably at least 0.4 ?
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How can I choose an airfoil for inverted flight & high weight payload?
I have a project for university to design and build a model RC aircraft. Tt's main design principal is to carry a high payload, so I was thinking of going for a high camber, thick aerofoil. Hopefully ...
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Poor airfoil choice for wind turbine
I am getting involved in an outreach project where I can modify a small wind turbine with different wing geometries. Are there examples of standard airfoil designs with particularly poor Cl/Cd ...
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F1A COMPETITION GLIDER
I am working on a school project. I have looked up the airfoil database. There is a wide range of airfoils I have tried to optimize for my glider to no avail. How do i choose the best airfoil for a ...
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Variable-pitch propeller blade design (AOA)
For a variable pitch propeller where the angle of attack can be adjusted during flight, are the individual blades similar in design to standard propellers, with a low angle of attack at the edge of ...
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How to calculate lift and drag of commerical aircraft in different phases of flight?
What is the best way to mathematically calculate values of lift and drag forces, in different phases of flight: takeoff, climb, cruise, descent, and approach?
Edit: I have the idea of calculating the ...
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What specific improvements were made in supercritical airfoil design from 1980 - 2000?
I originally asked a question (Comparisons between the A340 and 747-200 wing: sweep angle and span) about the technological developments which allowed the Airbus A340 to have a wing with greater ...
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What naca airfoil is the closest to airfoils used by modern airliners?
I know boeing and airbus use propietary airfoils, but is there a single naca airfoil that is fairly representative of what modern airliners use?
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Converting 2d Cl to 3d [closed]
I am trying to convert 2d Cl data obtained from javafoil for a NACA 4412 into 3d data to be used for analysis of the airfoil, but cant find any equations online
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What is a "suction airfoil"?
I just stumbled upon this entry on airfoiltools.com:
http://airfoiltools.com/airfoil/details?airfoil=griffith30symsuction-il
There is basically no information there and (a quick cursory) web search ...
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What’s the horizontal and vertical tail airfoil and volume of 747-400? [closed]
What’s the horizontal tail volume coefficient of 747-400? What’s the vertical tail volume coefficient of 747-400? What’s the horizontal tail airfoil of 747-400? What’s the vertical tail airfoil of 747-...
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Never heard of this Aerofoil?
I just came across this aerofoil, 65-2xx?
I searched this but it doesn’t come up with anything like 65-200 for example but instead SG6051 which is the closest I could find to this?
Am I missing ...
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What airfoil is used for the Dash-8 Q400?
Can't find confirmed information, only one I found was here https://m-selig.ae.illinois.edu/ads/aircraft.html, an incomplete guide to airfoil usage...
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How reliable are the available airfoil data sources?
I am making calculations based on Blade Element (Momentum) theory (BEM) for propellers and I am trying to find the angle of attack at which the propeller performs most efficiently.
If I have ...
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Is there an equation for how fast air accelerates into lower-pressure regions?
I’m designing a propeller, and I want to plan the shape of the trailing edge of each blade such that (as much as reasonably possible) the pressure comes out as an “equal” line.
Thus - I'm wondering ...
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What is the airfoil of the Tecnam P2002?
Does anyone knows what airfoil is used on Tecnam P2002? I need it for my report but I can't seem to find anything from the internet.
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Find Cl from Cp values [duplicate]
i have a code of the panel method where I can calculate all the Cp values.
my job is to calculate the Cl from these Cp values, and I understand that to do that I have to integrate the Cp over the ...
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The Effect of Pitching Moment on Aircraft Stability
I'm designing a small RC plane and I'm currently at the first iteration of airfoil selection. I have converged to Clark-Y, NACA-2412, NACA-2415, and S-8036.
In comparing the four, I noticed that all ...
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How to solve normal and axial aerodynamic force coefficients integral equation to calculate lift coefficient for an airfoil?
$$ c_n = \frac{1}{c} \left[ \int_0^c (C_{p,l} - C_{p,u}) \, dx + \int_0^c \left(c_{f, u} \frac{dy_u}{dx} + c_{f,l} \frac{dy_l}{dx} \right) dx \right] $$
$$ c_a = \frac{1}{c} \left[ \int_0^c \left(C_{p,...
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On which point are the moment coefficients of the NACA airfoils measured? [duplicate]
On airfoiltools.com website, for example: NACA 2412, they give airfoil data. One of it is the moment coefficient of the airfoil vs the angle of attack of the airfoil. However, these moment data could ...
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How can a small airflow that passes through a slots redirect all the outer flow?
If this is normal wing without slots behind wing will be huge wake; airflow will separate, which is very easy to predict.
Why would the outer flow follow the wing's couture; how can a small airflow ...
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How to calculate the takeoff speed for a hypothetical aircraft?
Given some basic information such as:
aircraft weight
wing load (including wingspan, and basically the whole wing configuration)
airfoil profile
coefficient of lift
angle of attack
Is it possible to ...
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Is it possible to have a separated boundary layer without having reversal flow?
To fix the ideas, let's consider an airfoil instead of a generic shape.
As far as I understand, the separation of the boundary layer takes place after there is a region of reversal flow on the suction ...
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Can I assume that aoa on horizontal stabilizers correspond to aoa of the main wing?
I am in the process of designing a small wing (Re ~ 50-100k) and am wondering if given (a) the Cm on the main wing is relatively small at low aoas, (b) the horizontal stabilizer will produce lift as ...
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Does wash-out reduce drag?
I am in the process of designing a small wing (Re ~ 50-100k) and was planning to "un-twist" the tip of the foil by -5°. This corresponds to the 5° aoa where the center part of the wing has ...
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How to turn inviscid data to viscous?
I have used Panel method to calculate Cp vs x/c graph and CL. But as panel method assumes attached flow it does not give an flow separation and thus in CL vs alpha graph I could not find any stall. My ...
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Why aren't HLFC panels mounted on wing?
I watched The Insane Engineering of the 787 by Real Engineering. He just gave short detail about the HLFC(Hybrid Laminar Flow Control) panel and mentioned their purpose isn't available online. I found ...
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How do thick and thin airfoils compare in lift generation?
I find myself confused when comparing the lift generation amongst Thick and Thin Airfoils.
A paper to which I have added reference below claims that thin airfoils are better in generating lift because ...
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Why are there two local maximums on some CL vs AOA curves?
I know what a stall is but I don't understand why there are in some cases two local maximums on the $C_L$ vs AOA curve of some airfoils. What is the reason for the mini stall that occurs before the ...
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What is a laminar airfoil and what are their pros and cons?
I am wondering what is a laminar airfoil and what are their advantages and disadvantages if compared to other designs.
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Circulation around an airfoil at negative α
I was recently reading this very helpful string What is the physical meaning of circulation found in Kutta condition? and it explained very nicely potential flow around an airfoil. My question then is ...
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What do these terms related to airfoils mean?
I keep coming across some terms related to airfoils and I'm not able to find clear definitions for these terms.
Bubble ramps
pressure recovery
suction side
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Are empennage airfoils always symmetric in conventional airliners?
I'm specifically interested in these models: A319, B737-700, A220, E195-E2. You could call these conventional airliners, so I suppose the question is if these "conventional" planes have only ...
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Wing and horizontal/vertical tailplane airfoil type and relative thickness?
I've been searching for data on the airfoil type (namely if they are supercritical, aft-loading etc.) and relative thickness (average or in different positions) of the empennage (both horizontal and ...
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Servo-actuated aerofoil
I intend on calculating the the servo torque required to actuate a 75mmx38mm NACA0012 airfoil. The example at the end of the page in the link https://github.com/build-week/hover-jet/blob/feature/start-...
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How do i find a supercritical airfoil for my preliminary design?
The following information is available but i don't exactly know where to get the information about SC Airfoils from. Do Airbus , Boeing use secret airfoil that they don't disclose?
Cruise Speed = 240 ...
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What is the relationship between the design lift coefficient and the section lift coefficient of a NACA5 airfoil?
I would like to know the relationship between the design lift coefficient Cli, of a 5-digit NACA airfoil, with the expression Cli = 0.15*L according to Wikipedia. And the section lift coefficient of ...