Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [blade]

A blade is a thin section of material designed to push or be pushed by a flow. This can be a turbine blade which makes up the compressor or turbine section of a gas turbine, or the blades of a propeller or rotor.

0
votes
0answers
91 views

How much do the blades on the V22 or AW609 weigh?

It seems that the blades on the V22 or AW609 would have to be heavier than conventional helicopter rotor blades since they have to be substantially stiffer when in fixed-wing mode. Normal helicopter ...
1
vote
0answers
18 views

How is the inflow velocity distributed of a tilted and trimmed rotor in hover?

I'm wondering of how the inflow velocities per blade look during one revolution of a real-life helicopter in hover (no inflow velocity into the rotor plane) with a tilted rotor plane about 20 deg. Is ...
0
votes
1answer
193 views

Is low pressure compressor air used to cool turbine blades?

This photo shows LP cooling air is being used to cool turbine blades. the question is, is it possible to use LP air to cool the turbine blades? would you please guys explain why do they use LP air ...
3
votes
1answer
231 views

Is the rotor described in this Kickstarter new?

A NewAtlas story linked to a Kickstarter for a the "Whisper Drone" that shows a CAD model of a rotor that the Kickstartee-aspirant has apparently 3D-printed and flown (four of) on a quadcopter. I ...
1
vote
0answers
138 views

Why don't helicopter rotors use curved blades? Curved from the top view. [duplicate]

I'm studying blade element analysis and I tried applying it to curved rectangular blades instead of straight ones. It doesn't really show any significant changes in the inflow ratio computation. Why ...
7
votes
1answer
364 views

Are engine casings expected to contain turbofan blade fragments?

On Southwest 1380, initial indications are that a fragment of the engine blade pierced the engine casing, which then hit the airplane window (or perhaps a part of the casing did). According to the BBC,...
2
votes
3answers
1k views

What is the difference between axial compressor blades and centrifugal compressor blades?

Is there a particular difference? The way they're overhauled is the same ? (I mean do we use the same overhauling methods ?)
0
votes
0answers
30 views

Will two blades or three blades last longer on a hobby drone? [duplicate]

Will it be better to run a lighter 2 blade prop vs a heavier 3 blade prop for longevity and battery life? they are the same length. I am curious if the extra weight of the third blade will inhibit the ...
1
vote
0answers
137 views

How are turbine blades overhauled?

How are turbine blades overhauled? What techniques are commonly used and how does it affect the integrity of the blade?
0
votes
0answers
34 views

What is the regulatory process for new blade/fan/vane approval in the US?

What is the regulatory process for new blade/fan/vane approval in the US? and When is regulatory approval required? For example, if I am currently helping to make already approved parts it is not ...
25
votes
2answers
5k views

Which manufacturer produced this fan blade?

I acquired a fan blade a few years back, but have not had any luck finding out who manufactured it or what engine/aircraft it may have come from. The only data I can find on the blade is as follows: ...
-1
votes
1answer
259 views

What is the market size of high-pressure turbine blades for commercial aircraft? [closed]

I need to calculate the market size for high pressure turbine blades which are used in commercial aircraft. I am working on a business school project on this topic. Any information which can be used ...
4
votes
1answer
728 views

Do fan blades use bell shaped lift distribution curves?

Seeing the organic curvature of some newer fans in turbofan engines, I'm curious if they use bell shaped lift distribution curves in their design, or something else all together.
5
votes
1answer
955 views

What is the fan tip speed at maximum thrust?

What is the fan tip speed at maximum thrust? Is it any different for a Rolls-Royce Trent 900 (powers the Airbus A380) and Pratt & Whitney PW6000 (powers the Airbus A318)? Are they efficient at ...
1
vote
1answer
1k views

How can I calculate the thrust of a fan given the diameter of the blade?

How do I calculate the thrust of a multicopter fan blade from its diameter? I am searching for a multicopter blade that can provide a thrust of 15 - 20N. Being someone who doesn't have any ...
3
votes
0answers
108 views

How do active blades work on helicopters?

Can someone throw some light on 'active blades' as used in helicopters? I'm mostly interested in the use of piezoelectric material and actuators. How are the actuators able to sense the change of ...
13
votes
2answers
1k views

What engine are these fan blades from?

I bought these from a metal scrapper and paid about $30.00 total figuring they're worth more than that in cool factor. Problem is they aren't nearly as cool if I can't figure out what engine (and ...
2
votes
0answers
191 views

Is there an engine database that would include information on number of HPT blades per engine?

I am attempting to compile information on the number of high-pressure turbine blades across a wide range of turbine engines. Currently, I have only been able to find this information through brut ...
1
vote
2answers
1k views

How to design the blade twist angle in propeller design?

I am designing a scale propeller for small UAVs and I have computed blade twist distribution for the blade airfoil sections. While I was modelling the propeller I have set the angles to twist about ...
4
votes
1answer
647 views

What is the longevity and replacement schedule for turbine engine blades?

I'm trying to understand how frequently hot section turbine engine blades are changed out. Is this a calculation based on flight hours, material, engine size or maybe something else? Apologies if ...
3
votes
2answers
4k views

Why do jet engine fan blades have a twisted shape?

is this a good answer. the blades rotate, the tip moves faster than the hub. So to make the blades efficient, the blades are usually twisted. The angle of attack of the blades at the tip is lower than ...
2
votes
2answers
173 views

Does the compressor stationary vane have stagger angle?

Does the compressor stationary vane have stagger angle? ( stagger angle is the angle between chord of the blade or vane with engine's longitudinal axis )
1
vote
0answers
156 views

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 ...
4
votes
3answers
1k views

How does the relative wind on a propeller, strike the blade from behind (the non camber side)?

This may be a stupid or simple question, although any help is appreciated! :) If possible, please answer without mathematical terminology. So I understand the concept of the blade increasing air ...
4
votes
1answer
708 views

What could cause a low-pressure compressor first stage blade of a turbofan engine to bend forward?

What could cause a low-pressure compressor first stage blade of a low-bypass turbofan engine to bend forward? I also noticed rotor path rubbing in the 9 to 12 o'clock portion (while usually this can ...
11
votes
2answers
2k views

How are helicopter rotor blades balanced?

Reading this answer, I realized that the balance of a rotor is critical. When one blade is changed, the whole balance of the rotor may be affected. Moreover, I doubt 2 blades are exactly the same. For ...
30
votes
4answers
9k views

Why are the fan blades mounted loosely?

In this question it is mentioned that the fan, compressor and turbine blades are mounted loosely in the disc. This is well demonstrated by this video posted by RedGrittyBrick. What is the reason for ...
4
votes
3answers
7k views

Why don't helicopters prefer shorter rotors with more blades? [duplicate]

My understanding of helicopters is that, despite theoretically increasing efficiency, longer blades are worse in practice than short ones in every respect (except, perhaps, cost): Longer blades are ...
17
votes
6answers
5k views

In helicopters, why not have electric motors controlling blade pitch?

From my related question comes this idea of electrically controlled blade pitch in helicopters. Control linkages in helicopter rotors seem to be pretty complex. This surely incurs a lot of friction, ...
-6
votes
1answer
1k views

How do the propeller blades accelerate air resulting in thrust to push an aircraft forward? [duplicate]

I do know that the blades on a propeller generate lift to provide a force pushing back on the air based on newton's law the 2nd. What I am having trouble understanding is how the blades generate ...
4
votes
2answers
1k views

Is it possible to get a list of Cl/Cd values for various NACA Airfoils?

There are a lot of links which give the shape of the airfoil for any given set of camber thickness, position and max. thickness values, but I would like to know if it is possible to get the Lift vs. ...
6
votes
2answers
266 views

What would happen if the blades of a variable pitch prop did not all have the same pitch?

What would happen if one or more of the blades (but not all) on a variable pitch prop would not tilt at the same angle as the other ones? Could this situation happen or is the technology so advanced ...
19
votes
1answer
3k views

Can you identify this jet turbine stage?

I was just wondering if anyone could give me any info about this turbine rotating stage I picked up at a yard sale today. The stage measures 8-1/2" to the outside of the blades. The only markings I ...
19
votes
2answers
20k views

Why are aircraft turbine blades made of nickel alloys?

Why are aircraft turbine blades made of nickel alloys? What is the advantage of using them? Why did they replace steel alloys for turbine blades? How to overcome failure cases of turbine blades?