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-   -   Helicopter aerodynamics CD Rom? (https://www.pprune.org/rotorheads/142074-helicopter-aerodynamics-cd-rom.html)

Devil 49 13th Sep 2004 05:22

If all that refers the main rotor, the swept area is a "disk" and from some aspects, the "tip path plane"

Flingwing207 13th Sep 2004 05:24

er...

by "shaft axis", I'm supposing you mean the main rotor drive shaft?

"Axis of rotation" is tip-path plane?

Or perhaps I don't actually have a clue what you're asking. Well, I tried, anyway.:8

gadgetguru 13th Sep 2004 05:34

tip path plane
 
I've reserved the 'tip path plane' label for the illustration of coning angle in relation to the Plane of Rotation, which may or may not be the same as the Plane of Rotation relative to the Shaft Axis.

So i have been trying to segregate tip path plane from anything else. As I will also need to illustrate the difference of the disc area formed by the tip path plane during coning, in comparison to tip path plane in an otherwise 'normal' AoR.

by 'normal' i infer that the disc area is at its maximum, & coning is angle is zero

an AoR 'datum' would need to include a Plane of Rotation 'datum', so that as with the AoR vs Shaft Axis, the Plane of Rotation relative to each of these is illustrated (i think i've cocked up the explanation of that in the opening thread - apols)

the Plane of Rotation relative to the AoR will be the significant feature of the animation, it will also serve as a reference datum for the coning part of the animation

cheers

[email protected] 13th Sep 2004 06:05

On the ground, with zero wind and with the disc (tip path plane) parallel to the ground, the shaft axis and the axis of rotation are the same (providing the gearbox does not have a tilt in any direction).
When the cyclic is moved and the tip path plane changes (disc tilted forward for example) the the shaft axis remains the same but the axis of rotation has moved forward and is at 90 degrees to the tip path plane.

mike papa delta 13th Sep 2004 09:06

The diagrams in me trusty Norman Bailey book refer to this as the Cone Axis... (I think!)

gadgetguru 13th Sep 2004 09:41

breakdown of elements
 
Thanks Crab

as per picci on the preceding page
the green axis is shaft axis
the green circumference / plane of rotation is the 'datum' that i am refering to, as you described relative to shaft axis

the pink/magenta axis is the 'new' axis of rotation (shifted away from shaft axis by - in the illustration fwd cyclic input)
the pink circumference / plane of rotation ( relative to new AoR) is the tip plane path with zero coning.

if you can imagine now a 3rd circumference / plane of rotation above & parallel to the pink one, slightly smaller, being the disc area & tip path plane under a load (coning), hence i am wanting to maintain each element seperately so that the students can see it happening & have a reference point for each one.

the missing link sort of stuff...

might be easiest if i produce a still shot of what i am trying to describe with the labels as i see them , then get your feedback

i don't want to produce something that is going to generate any arguments over the terminology used.

thanks again for feedback

gadgetguru 14th Sep 2004 01:26

a picture tells a thousand words
 
the picture below should allow for an easier explanation of what i am trying to achieve

full size pic with all labels/detail is available at :
http://holeygrail.khanted.com/graphics/cone_tpp.jpg

http://holeygrail.khanted.com/graphics/tpp_thmb.jpg

as the MR blades (Pink) travel & TPP/PoR (also pink) move with the changes in AoR, there will be a ghost set of blades following (what i have termed the) the PoR 'datum' (Green) relative to the Shaft Axis (Green)

the student can then see where the TPP/PoR has moved to with any given cyclic inputs in relation to where it started from.

at the point where coning is introduced, in order to reflect the position of the TPP (with coning) in relation to the 'normal' TPP relative to AoR, another 'ghost' set of blades will maintain the PoR about the AoR, whilst the Actual Blades (Tips) will raise (cone) & the disk area (transparent orange disk) will contract as the TPP increases above the PoR.

the final product will include a simple fuselage, with some extended (long/lat) axis lines so that the perspective view is easier to interpret specifically in regards to the disc tilt
cheers :8

should i consider demonstrating Disc tilt (AoR shifts from Shaft Axis)
to coning (TPP under increased load) seperately to reduce the amount of information needing to be assimilated?

then have this (pictured above) as the 3rd collated detail.

one step at a time...

would appreciate any views

gadgetguru 19th Sep 2005 22:26

Type (Tech) Profile imagery
 
Hi all, the slow painful process of 3D animation of aerodynamics has begun

I need to source some Helicopter technical diagrams (profile shots)

Does any one have any good resources of technical diagrams, like those in the flight manuals - which i don't have access to

I currently have
Bell Jetranger
Robinson R22/R44

I need to source the following:

Bell 47 (asap)
Hughes 500
AS350
Sikorsy S76
EC120 &/or 130
Bell 205/212 (412 I can get from their website brochures, but need the older models)

If anyone can provide links or even scanned images of these types from manual pages, I would be most appreciated.

Cockpit layouts would also be usefull later on, however the fuselages are the priority at the moment.
:8

Bosbefok 20th Sep 2005 00:05

Looks good but you're re-inventing the wheel - comprehensive pc-based training software is available. The bad news - it's aimed at training schools etc, and therefore very expensive. Starts with the basic functions like the internal combustion engine etc and continues on to turbines, instrument flight etc etc, all in step-by-step format that closely follows the training syllabus. Rather large - installs from a 5-cd set. My advice - source a school that is equipped with the latest in training aids such as this, and one with a simulator is a bonus.

gadgetguru 20th Sep 2005 04:26

3D visualisation applies to everything
 
just because you may not be a school, doesn't mean you don't need it.

3D visualisation is something that most companies could do with, but have not yet realised it, & is flexible enough to be applied to any custom requirement.

it might be expensive, but it depends whether your paying for quality, speed
&/or both.

doesn't solve my problem though - i still need the pics.

anyone?


cheers

paco 20th Sep 2005 04:40

Gadgetguru

Look in a book called Helicopter Maintenance - there are a lot of techie diagrams for quite a few helicopters in there.

As it happens I am shortly to go for approval fpr a JAA CPL(H) distance learning course - give me a PM with your real email - perhaps we can talk about a few things

Phil

Tony Chambers 20th Sep 2005 20:14

3D imaging is definately the way forward, i'm not a pilot but as part of the service i provide in groundcrew training i am now looking to get a whole new load of simulation, emulation, 3D images and simulators produced. If you want to beef up what you already have with the 3D stuff may be we could chat and i could posssibly talk to the guys who will be doing the stuff for me.


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