Linked Questions
21 questions linked to/from How does a fan differ from a propeller?
11
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3
answers
5k
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At what point is a turbine powered ducted propeller considered a turbofan?
Turboprop Propellers can be ducted for extra thrust. What are the criteria for determining that the engine is no longer a ducted propeller design, but a turbofan? Does there have to be a type of ...
- 373
9
votes
3
answers
6k
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How does blade solidity ratio relate to thrust/power/torque of a propeller?
for quite some time I was using ABBOTT formula for static thrust estimation on a two-bladed propellers:
$$
T=6.8\times10^{-5}\times D^{3}\times p\times RPM^{2}
$$
$T$ is Static Thrust (N); $D$ is ...
- 631
32
votes
2
answers
44k
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What are the advantages of more than 4 propeller blades?
I have heard that propellers with more than four blades are not as efficient as 4 or less blades because of lower thrust which may result from interfering prop-streams. But I see the ATR-42/72 and ...
- 12k
23
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2
answers
5k
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Why aren't there any widebody propliners for the high-density short-haul markets?
Jetliners come in both narrowbody (one aisle) and widebody (two or more aisles) versions, but all propliners, to the best of my knowledge, are narrowbody aircraft.
Now, granted, one of the big ...
- 28.3k
13
votes
2
answers
4k
views
Why is the bypass ratio of a turboprop higher than turbofan?
Whenever, I come across turboprop, the author always mentions that they have higher bypass ratio than turbofan but no one explains the reason for this.
So, is the bypass ratio higher due to higher ...
- 741
8
votes
2
answers
2k
views
Could ducted propellers improve efficiency in small drones?
I have seen that a new electric airplane design has decided to a choose ducted propeller design somewhat similar to the one of jet engines, explaining this design choice with the fact the ducted ...
- 181
7
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2
answers
4k
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Is 1 propeller always more efficient than 2?
Based on other answers I've read here (1) (2) (3), a single large blade propeller is the most efficient type of thrust you can get.
There are 2 reasons for this (as I understand it). Firstly, ...
- 1,211
5
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2
answers
1k
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Do any propellers/propfans use stator vanes? Why is this not a commonplace feature?
I understand that axial-flow turbine engines generally include stator vanes behind every(?) compressor and turbine stage. This makes quite intuitively sense, because without them the rotating blades ...
- 784
4
votes
2
answers
636
views
How does one choose the number of blades and the diameter required for a turboprop propeller?
I am interested in the preliminary design of a regional aircraft that uses turboprops as the propulsion method.
Following considerable research online about propeller design (disk theory, BEM...) I am ...
- 75
1
vote
2
answers
498
views
Do aircraft travel faster at higher altitudes?
I'm aware of the difference between TAS and IAS, and how IAS gets lower in reference to TAS as you climb and the air gets thinner. What I'm trying to figure out is whether or not an aircraft's IAS ...
28
votes
1
answer
18k
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Is there any equation to bind velocity, thrust and power?
I am designing a remote controlled airship. I will tune it so that the lift given by Archimedes' Principle will exactly balance the weight of all the structure. It will be propelled by brushless ...
- 383
22
votes
1
answer
7k
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Why don't aeroplanes use propellers with more blades like the intake on a fanjet?
The air intake on a fanjet typically has many small angled blades. A wind pump in an American film might have many broad slatted blades. My desk fan has 3 very large scooping blades and seems quite ...
- 323
2
votes
1
answer
310
views
Is NASA's X-57 using a fan, a prop, or a prop/fan and what is the difference visually/physically?
Is the NASA's X-57 or the Opener BlackFly using a fan, a prop, or a prop/fan and what is the difference visually/physically?
NASA X-57 Maxwell, courtesy of Wikipedia
Opener BlackFly v3 courtesy of the ...
- 1,243
1
vote
1
answer
419
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Is there any equation on propeller thrust that takes into account the number of blades [duplicate]
I had a look at both
What is the equation for calculating static thrust?
and
Is there any equation to bind velocity, thrust and power?
However, it does not mention how much would the thrust be ...
- 11
1
vote
1
answer
1k
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In what way are the airfoils used for a propeller different from the ones used in turbofan engine?
Airfoils are used in the blades of a propeller as well as the blades of the fan, axial compressor and turbine in a turbofan engine. Thus, the airfoils used in above two applications have different ...
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