Questions tagged [propeller]
Aircraft propellers are airfoils which convert rotary motion from a piston or turbine engine into thrust suitable for propelling an aircraft.
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Do constant maximum lift to drag ratio variable pitch propeller exist?
Are there variable pitch propellers, where pitch is set so that the blades constantly are at their maximum lift to drag ratio AoA, whatever the incoming relative wind speed & direction?
Such a ...
user21228
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What is the aerodynamic influence of prop spacing and placement in multi-prop engine setups
I saw this question Is there a rule of thumb for spacing between jet engines?, which referred to How do you choose engine placement for under wings engines?, but I was wondering how the engine spacing ...
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Has a carbon fiber propeller ever broke with a bird strike?
Curious if a carbon fiber prop has broken(or considerably deformed) with a bird strike. Or maybe by something else other than an impact with the ground/crash.
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Is there a convention of propeller tip separation from the wind tunnel walls?
Blockage ratio is commonly used to address the effect of confinement on the propeller's performance tested inside a closed test section of a wind tunnel. In most cases, blockage corrections (like ...
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What calculations are needed for counter-weight balancing on a propeller?
I am designing a small-scale propeller and i have managed to design on optimized geometry for the blade. However the blade pitch angle adjusts according to different flow speeds so i need to mount ...
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What Inertial effects should be considered to achieve blade stability on a Variable Pitch Propeller tailoredby aerodynamic loads?
I am developing a self adjusting variable pitch propeller tailored by its pitching moments due to aerodynamic loads setting the blade rotation axis in an offset from the aerodynamic center as shown ...
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What is the history of this specific Cessna propeller (s/n F2430)?
Hoping someone can help... I'm looking to get some information about a Cessna plane propeller my Fiancé recently bought. It's his birthday coming up and it would be great to have any sort of history, ...
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Could a WW2-era Grumman Hellcat land on a Saipan-class light carrier using only reverse-thrust generated by a reverse-pitch propeller?
Just that - take away an F6F's arrestor hook and fit it with a reverse-pitch-capable propeller (and, of course, all the other odds-and-ends to make such a system work).
Would it be possible for a ...
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How to retrieve the thrust distribution over a blade using XROTOR?
What is the procedure for retrieving the thrust distribution over a propeller blade using XROTOR? I need the sectional (i.e., for each station) thrust coefficient values.
I was only able to retrieve ...
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Would the dle 55ra engine be enough to power my paramotor(ducted fan)?
I plan on using the dle 55ra engine to produce 5hp at 8,500 rpm. I am using it in a paramotor, and to save space I am considering using a ducted propeller similar to the Fulcrum power pod. The duct ...
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Why have supercritical airfoils not been used in designing the propeller blades?
In terms of specific fuel consumption, propellers are more economic than jet engines at low speeds (<0.5 Mach) but at high speeds, the propeller blade tip reaches locally to supersonic speeds which ...
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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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Calculating the Thrust vs RPM Relationship of a Brushless DC Motor
hope everyone is doing okay.
I am conducting a project with my friends for an Unmanned Aerial Vehicle. We are first using MATLAB - Simulink to design and simulate the quadrotor. We completed the ...
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Is "V/n" geometric or effective pitch in advance ratio formula?
V is the freestream fluid velocity, typically the true airspeed of the aircraft or the water speed of the vessel
n is the rotational speed of the propeller in revolutions per unit of time
D is ...
user52248
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Could propellers benefit from the design of the Blue Edge rotor?
Source: wired.com
If indeed the Blue Edge blades reduce noise by 50%, could the similar design be used on [forward-facing] propellers without a penalty in speed or agility?
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What airplane model was this historic propeller attached to?
I have a 9-foot historic wooden biplane propeller with brass edges. It does have a serial number, but it is tough to read. 2250 DN 152 6' 6" is what it appears to say. I am attaching a photo of it. ...
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Do open propellers experience pre-entry drag (additive drag) like an engine in nacelle?
Engines in a nacelle experience pre-entry (also called additive) drag.
Do unducted propellers experience it too?
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What is the relation between solidity and lift coefficients?
I've seen this graph in a couple of places. I'm not sure what it's supposed to mean, as the formulae I've seen in the papers cannot be found in any standard book or reference.
Please let me know if ...
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Compute Thrust from RPM and Induced Velocity
I'm attempting to calculate the difference in thrust in a secondary propeller operating in the wake behind a primary propeller, in the context of a trailing quad-copter following a leading quad-copter ...
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How to compute actuator torque requirement for Variable pitch mechanism??
Suggest me any reference to compute the torque requirement for actuator/motor to control the pitch angle of propeller (Variable Pitch Propeller).
Thanks in advance
Arun Ravindran
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How does a partially covered air intake affect the thrust of a propeller ?
does a partially covered air intake of a ducted propeller significantly affect its thrust?
If so, will it be like 10 or rather 90 percent less thrust ?
Thanks for your answers!
Simon
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What causes these losses in this propeller simulation?
While running a CFD simulation comparison of 2 vs 3 blade propeller versions (48" diameter, 23" pitch, 3570RPM), I've come up with:
2-blade: 347N of static thrust @ 110Nm Torque
3-blade: 220N of ...
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why are airplane propellers always undersized?
While calculating propeller static thrust by using a famous Prop-power-calculator.xls (by Pé Reivers),
I've noticed that no matter what "stock" configuration I put into the calculator, I do always get ...
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XRotor blade angle distribution
My question is about the XRotor definition of the blade angle distribution (beta), which XRotor solves for or requires as input. Is the blade angle on XRotor defined as the angle between the rotation ...
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how can we calculate normal force or vertical component of propeller in an aircraft?
when we calculate thrust of an propeller engine we also face to vertical component or normal force which change neutral point of an aircraft how can we calculate this force? thank you
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Deriving Accurate Exit air velocity of rotor
My goal is to derive the equation for exit air velocity as a function of:
Pitch angle
RPM
Rotor Radius
Constants like ρ
Assumptions:
Vc is relative velocity of air upstream, and is = 0
Inflow is ...
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where is the centrifugal force the flyweights experience coming from?
The T6b uses a PT6-68 engine which has a variable pitch, constant speed, feather, and non-reversible prop system. There is only one lever in the cockpit which regulates Torque and the Power Management ...
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What is the meaning of "Contra-Rotating Propeller Increases Efficiency"? How is it calculated?
This picture is taken from here.
In that video is mentioned that contra-rotating propeller increases efficiency up to 6-16%. Regardless of the number that could be vary from one airplane to another, ...
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What is propeller pitch speed?
I was using Ecalc to calculate some flight parameters and then I came across this term called "propeller pitch speed". Can anyone explain me what this means?
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Is pitch-flap coupling an aerodynamic effect or an intrinsic property of a delta 3 offset?
I am modelling a propeller, in particularly the equations of motion of the various pitch/lag/flap angles as the propeller is turning around. The blade includes a $\delta_3$ angle, which provides pitch-...
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What is the effect of moving a propeller closer to a wing?
Does it improve efficiency?
What if the wing is just a plate? Certainly increasing plate thickness will decrease efficiency.
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What is a good and simple software for calculating propeller thrust and required power?
My main requirements:
Calculate propeller thrust with big range of the altitudes (0 - 200 km) or to have air pressure input parameter, which I can type. For example pressure for 152 km is $4.98\...
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What kind of propellers are generally mounted on the Aeriane Sirocco?
I'm curious what propeller is used for the Aeriana Sirocco. Online I see lots of pictures of propellers with three blades, but none with only two and I cannot find many clear pictures of the proppeler....
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flow rate through a propeller disc
Let's take the case of a stock Cessna 150, chained to the ground, standard day conditions. The engine is running at full power (say 2500RPM) and the propeller is absorbing its full output. Is there a ...
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Propeller air displacement
I was thinking about propeller design just now and it came to mind that, theoretically, the air displaced by the propeller after every rotation might not be able to "flow back" into the area "served" ...
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What velocity is used to calculate maximum range and maximum endurance?
These are my data;
$C_{L_0} = 0.4$
$C_{L_{\alpha}} = 5.7$
$C_{L_{minD}} = 0.14$
$C_{D_{min}} = 0.022$
$k = 0.035$
$\alpha_{stall} = 15$
$S_{ref} = 20m^2$
Mass Data
$W_{total} = 2500 \text{ kg}$
$W_{...
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Fly a fixed wing single propeller airplane like a helicopter?
Has anyone tried to "helicopter" an airplane? And succeeded? And posted this video on the internet where I can find it?
What I'm talking about with what I would call a "helicopter&...
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