'Singing' wings

[sirenoremac 0]

Okay, I'm going to take another whack at this, and try to explain, NOT shoot down for no reason, but explain WHY your idea doesn't make sense. I am not an enemy. Clear? Okay. Here goes. First off, the principle that a ramjet operates on is simple. It is in essence just a venturi with a fuel injector. The venturi itself adds NOTHING to the system. It's the energy from the combusting fuel that gives a ramjet the ability to accelerate. Otherwise it is as Kallend said, just a funnel being dragged through the air. Now what you suggest is to use gravity as your powering force, and use flare of a canopy as an example. Conservation of energy not only allows for that, but it is also a very simple and good example of the law. When a canopy is flying at 100 feet, it has both gravitational potential energy, and kinetic energy. The idea behind a swoop is to convert as much of that potential energy into kinetic energy with as little energy lost to friction as possible. Then, if the timing is perfect, when the kinetic energy of the skydiver-parachute system has reached its peak, and the canopy is in a dive with forward movement, you then use the remaining kinetice energy (speed) to generate lift. Then as the canopy slows, the swoop comes to an end, setting the skydiver down. Are we good? Make sense? Wonderful. Now here comes the biggest problem with your little thought. Remember how I mentioned that for a perfect swoop you want to convert potential into kinetic with as little loss to friction as possible? What do you think adding holes is going to do? Besides the fact that it will weaken the pressurization of the wing and therefore be non-beneficial, you are also presenting more parasite drag to bleed energy away. Enough to immediately equal and quickly outweigh any possible hope of adding lift to the system. You were hollering about dynamics assuming a perfect world. You are the one assuming perfection. You have to remember to account for non-conservative forces as well. Besides that, which is the most obvious mis-step in your plan, you still haven't said anything about what will happen with the topskin forces of the airfoil, or how you think the loss of rigidity on the whole will affect performance. Short answer: negatively. Your net lift will only increase by adding energy into the system, or by making the system more efficient in and of itself. Adding holes to the bottom of a RAMair wing will NOT increase it's efficiency.

[Trae 1]

MMMMmmmmmmm ......................................................OK I feel like I can be trusted to stay on topic here...I'll give it my best shot anyway...

in reply to " First off, the principle that a ramjet operates on is simple. It is in essence just a venturi with a fuel injector. The venturi itself adds NOTHING to the system. It's the energy from the combusting fuel that gives a ramjet the ability to accelerate."

This isn't completely correct. A ram jet will only operate when it is already at a speed where the air entering the inlet is compressed sufficiently for the jet to work( and then it can be accelerated as you say by burning fuel in the compressed air and expelling it out the back at high velocity )
Therefore the inlet shape DOES have something to offer by actually taking the place of the more normal compressor stages that are used in say a double shaft jet turbine.

If you just light up a ram jet motor on the ground while it is static the air is not compressed enough for the ramjet to operate. ie ramjets NEED to be accelerated to an operating speed before they will work. ..very efficiently at high speeds apparently because they have bugger all moving parts.

in reply 2"you then use the remaining kinetice energy (speed) to generate lift. "


The energy being added in my now archaic idea is similarly produced by xtra speed achieved during a dive....excess energy which may have previously not been required for inflation or even available during a flare due to the limits that the present designs have in this respect.

As regards the top skin ..as this is where approximately 2/3 of the lift is generated the extra speed by providing xtra inflationary forces and having an excess of these forces is not such a problem as 'assumed' (in my visualisation).

It is these extra or excess forces (available due to the higher diving speeds being achieved) which I am proposing MAY be useable to help create lift rather than just ballooning the canopy (thereby creating extra drag)with the extra air being forced into the front inlets at those higher speeds.

By improving the micro boundary layer on the bottom surface somehow eg pushing higher pressure through the 'pin holes" it is potentially capable of upping the lift factor. (sort of like a fluid flap)

Similarly on the top surface some form of micro boundary layer improvement may be obtainable similarly to say a slat or blown wing (on a micro layer level)

I know these concepts are already being used ..it's just that they're normally provided by jet efflux not the extra energy available during an extreme swoop or wingsuited flare as I'm proposing.

The trick here and the difficulty of achieving this design in the real world would be a fairly complicated balancing act as of course the canopy has to maintain enough internal pressure to keep a suitable wing shape.

Just because no-one has integrated such concepts into a canopy or wing-suit design is not an argument against their potential validity.

Whew ...... This is teaching me ingleesh as well as aerodynamics ...who would have guessed.?

Not me.


edited cause I at least wanted to get the spelling correct

[Trae 1]

in reply to myself
Been havin’so much fun trying to describe aerodynamic ideas of late that just HAD to run another idea past this arena . There are some similarities here so still on topic

This one is basically SLOTTED FLAPS for ram-air canopies . The basic idea is that during the flare a slotted flap is lowered at the rear of the canopy to increase lift
This idea is in conjunction with an air-locked rear third of the chord.

This air-locked rear section is meant to provide stiffness and structural integrity to the part of the canopy that is pulled down by the brakes. During a ‘ normal’ brake flare with a ‘normal’ canopy there is some distortion to this rear part of the canopy. There is also a redistribution of the internal pressure which affects the overall performance of the flare and the wings lift capabilities.

It is hoped that even without the addition of the slotted flap the rear section airlock could provide lift advantages during the flare ( and in certain manoeuvres) by itself by providing a more consistent stiffer section less affected by pressure redistribution.
With the addition of the slotted flap it is possible that any lift advantages may be further enhanced.

This is where it gets a bit wobbly............ If you can imagine a miniature ram-air flapextending over the whole or part of the trailing edge that for ‘ normal’ flight usually sits tucked up against the rear of the lower surface.

In the flare motion this ram-air flap is pulled down and operated much the same as a flap in an
aircraft . For example it may only come into effect below the half brake point..ie in deepish brakes.
The slotted bit allows for an airflow between the top of the flap and the lower trailing edge. The tech. for this apparently works well for solid wings with some designs being double or even triple slotted.

For starters a single slot may be applicable here.

The airflow over this flap could also potentially improve the upper surfaces rear boundary layer as this airflow (if placed correctly) could further delay the separation of the upper boundary layer by a rearward sucking effect .

A natural progression here is to then attempt to improve the airflow over the front top portion of the canopy during the flare by the use of slats. Once again the science for this is already applied in solid wing designs.

Having some form of pop-up slat that redirects the top surface airflow during the flare could have fairly obvious advantages to enhancing lift. The extra complication of such a design may make such enhancements difficult to apply to ‘normal’ skydiving canopies but this tech. MAY be more applicable in the areas where such performance gains may be worth the trouble eg swooping, distance during flare or just for people who want to maximise their canopies performance for their own reasons.


I must say this is not new or simply my idea as I’ve come across people in the parasailing community and the CRW world who have experimented with various flap designs. The advantages they gained did allow for certain lift improvements but these were often at the expense of overall drag increases and the gains appeared to only be available for a short time before the speed washes off too much due to the extra drag. However these short term gains may come in handy during high speed approaches when the extra speed can be rapidly converted into extra lift and given some extra design work may allow for enhanced high performance canopies.

Tuck up flaps and tuck down slats any-one?



Ps kinda proven the saying that a picture's worth a thousand words.

[The111 0]

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Tuck up flaps and tuck down slats any-one?

Here comes the free thought police! (me)

How do you plan on adding "flaps" or "slats" to a nylon canopy?

www.WingsuitPhotos.com

[nicknitro71 0]

1. Keep up the good work

2. Are you really sure you want flaps on a canopy?

When I want to make a flatter, faster, "swooper" landing with an airplane, guess what I do with the flaps? I leave them alone. Why? Because more flaps equals more drag, yes it also equals more lift but I guarantee you that if you manage to put flaps on a canopy the distance of a swoop will be drastically reduced.

3. I did not mean to be overly sarcastic and I apologise for that. However, your understanding of basic aerodynamics, or fluid dynamics, or even simple physics seems very limited. Then you go and start arguing with people who eat physics for a living and you want to prove them wrong making mindless arguments.

I took two semesters of physics in college and I am in no position to argue with anybody about physics due to my extreme ingonrance on the topic. IMHO you should listen more. This is not an attack by any means.

About the three-ring-system:

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(1)the need for constant maintenance
(2) their tendency to not let go during extreme circumstances ....
(3) the way they CAN be put together incorrectly...

(1) Constant maintenance? 1 minute a month is all it takes. Cutaway, clean the cables with silicone, massage the risers. How is that for constant maintenance? Also every system that I know of needs some maintenance: You car, your canopy, the airplanes you are jumping from, and your own body as well.

(2) Usually this is due to the lack of the one-minute-a-month maintenance, the lack of riser inserts, or a combination of the two. Please give a more specific example that does not include the two mentioned.

(3) Are you saying that you cannot put a canopy together wrongly? The tree-ring system is one of the simplest components to assemble in a rig not to mention its elegance. Think about. No tools needed and it takes about 30 sec to do it right and if in doubt you can always ask a rigger.

Memento Audere Semper

903

[kallend 1,623]

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But I agree, titty bars are fun.

You obviously don't understand the laws of physics.

Sorry, just trying to get this back on-topic to ridiculous arguing.

Rubbish. Boobies are perfect examples of the laws of physics in operation. Coupled harmonic motion of a forced non-linear visco-elastic system under the influence of gravity.

...

The only sure way to survive a canopy collision is not to have one.

[The111 0]

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Rubbish. Boobies are perfect examples of the laws of physics in operation. Coupled harmonic motion of a forced non-linear visco-elastic system under the influence of gravity.

Somewhere, somebody is turned on.

www.WingsuitPhotos.com

[voodew1 0]

Rubbish ---- is that some new form of masturbation?? Do tell I am starting to understand this thread now.

Boobies need some rubbishing

If i only understood the shit you guys talk I might be intrigued but I resort back to porn as I am not the brainiack mofo like ya'll

But even the overly smart can understand BOOBIES

The pimp hand is powdered up ... say something stupid

[sirenoremac 0]

Allright, back to civilized discussion. Thank you. As has already been said, the biggest flaw in your idea, and the one that I believe would kill any possible benefit is the production of extra parasite drag. In a prior post, it was mentioned that flaps on an airplane produce MORE drag than lift. The general figure thrown around is %30 more lift and %300 more drag. A 10:1 ratio. Remember that the key to making swoops longer is essentially making them faster. Clean up the drag, streamline the system, and more of your speed will be available to convert into lift. In more depth, your flap idea is essentially a more clumsy and complicated method of applying the same idea that canopies already use. When you put flaps down on an airplane, you are changing the chord of the wing. The same exact thing happens when you flare a canopy. In an airplane, in a no-flaps configuration on landing, the pitch, and angle of attack are controlled with the elevator. A parachute does not have the luxury of an elevator, and therefore must change the actual shape of its wing to control its pitch and angle of attack. When you flare, look at your canopy and notice (which I'm sure you're aware of) that the trailing edge is pulled down, creating a very similar visual to that of lowering the flaps on most small aircraft. So essentially, parachutes already come with flaps. We just happen to use them as our elevator and ailerons as well. Oh, and these flaps have been very precisely designed by the manufacturers to do their job as best they can for the type of canopy that they are on.

As for your original idea, once again, without any kind of model to go on and couldn;t say for sure, but I can pretty much guarantee that the added prasite drag, as small as it may seem, wouldn't kill any potential lift benefit. With a parachute we only have so much energy to work with, and we really have to figure out ways of more efficiently using that energy, so good for you on thinking forward. But the solution is not likely to be found in fairly complex systems, and much more likely to be seen as very clever small improvements to increase efficeincy a little bit at a time. Think cross-bracing for more rigid wings, think HMA lines for lower drag in the line system, think collapsible slider and pilot chute. And remember, there's the matter of skydivers liking soft openings. Adding to material in strange places or putting holes in a canopy are most likely not going to benefit a nice 500-700 ft on-heading opening. But then I guess we are really just talking about the pure aerodynaimc possibilities here. Oh, as for your point about using the air that is simply being wasted in making the wing more rigid, I don't believe that there is any wasted pressurizing air while a parachute is flying. Hence the need for cross-bracing, air-locks, and even better forms of internal bracing (PD's up-and-coming Z-bracing). In other words, there isn't any excess pressure in a RAM-air wing. If there was, perhaps some type of system could be implemented to use it more effectively, but I get the feeling that it wouldn't be putting holes in the bottom-skin of canopies. Anyway, keep tossing those ideas out, just don't get so defensive when people offer their expertise on why it probably wouldn't work. Life is learning. Let's keep up the discussion.

[Trae 1]

Ta for the criticisms,
All taken on board and some of it thrown back overboard.

Most of my knowledge of aerodynamics comes from direct experience tinged with an admittedly ancient flare for Dynamics of Machines and such.(you gotta love those multi -paged equations used to decribe the forces and motions of moving pinned levers and such in 3D.. I know I do)

Yes flaps will slow you down with their extra drag etc. (I too said that in my little blurb )...yawn

I feel most of your criticisms here are a product of misreading and misunderstandings on your part perhaps due to my poor grasp of the written english language... perhaps not. You can think I'm just a dummy and sprout those inferences ...so what?

As for the mindless argument bit ..that sounds like an opinion to me not a fact.

AS for the 'three ring ' system. I agree with what you've said here.... mostly
but that doesn't make the deficiencies go away.
I can put it all together usually but I see a lot of other people who can't. In the mechanical field any design that can be put together incorrectly is design deficient....self explanatory and taught during my time at University .
You must know that a lot of advanced mechanical designs can only be assembled correctly otherwise they just don't go together... these features are usually designed in- not just happy accidents.

It's my feeling that the three ring system is not perfect and as such can be improved on. This sounds logical to me but I'm sure the opposite could be argued .

However I didn't come here for an argument just to share 'a little flight of fancy' .(I still think its got some merit by the way)
I know the engineering mind often has trouble with creativity cause it's bound by all those "laws" and "rules".

I feel a bit sorry for the apparently negative personal responses (mindless, absurd, etc )I've had from just mentioning an idea.( that brought out negative responses from me..etc rebound etc etc )

I have learnt something here though and hopefully will continue to do so.

Cheers.

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[kallend 1,623]

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However I didn't come here for an argument just to share 'a little flight of fancy' .(I still think its got some merit by the way)
I know the engineering mind often has trouble with creativity cause it's bound by all those "laws" and "rules".

You should be very grateful that you are not bound by the laws of physics like us mere mortals.

...

The only sure way to survive a canopy collision is not to have one.

[sirenoremac 0]

I have tried very hard to keep anything I've said from being personally negative, 'cause I really don't have anything against you or your idea or you rright to share your ideas. All I've tried to do is point out the things about your ideas which I believe would make them impractical or non-beneficial. It's nothing personal, really, and it certainly is not an attempt to kill creativity for the sake of physics. It's merely an application of my knowledge of physics and aerodynamics to a presented thought toward which these fields are applicable. Because when it comes down to it things obey the laws of physics. Creativity isn't discouraged, you merely have to apply that creativity toward exploiting those laws as opposed to wishfully trying to ignore them. Not that that's what you are trying to do, but you do keep coming across as willing to let the aspects of physics which don't seem to work well with your idea slide on by. As for the three-ring system, I agree, it CAN be mis-assembled, and while that is something that is considered a design flaw in complicated mechanisms, there are really only four parts to this mechanism, and any misstep in assembly is easily caught with a cursory glance. Not to say that it's perfect, but it is a well tried system. If you have an idea for an improved system, or feel like you could come up with one, more power to you. That's where innovation comes from, not from whining about poor design, but from fixing it. Three-rings are an improvement from older systems, and we will keep using them until there is another clear improvement. I also would like to invite you to return arguement, instead of poo-pooing what we've said. If you still think your ideas have merit, tell us why. Like I said, I'd like some discussion, to get a better grasp on an idea that I have thus far only had a few lines of written description on. I may still not fully get what you're trying to put across, so explain it in more detail, and explain why you believe that you could create a benefit with the system. I've explained why I don't think you can. Return the favor.

[Trae 1]

G'day sirenormac ,Ta for your considered non-inflammatory replies ...appreciated.

I agree the 3 ring system is brilliantly simple and has transformed and simplified the cut-away process..and no doubt saved heaps of lives. I've jumped using cape-wells and tape-wells (1 1/2 & 1shots) and am glad to see their replacement .
I'm just a nit-pickin' perfectionist etc...

as to the slotted flaps ---- Of course canopies already have flaps we just don't call them that. Slotted ones are just more efficient in some applications.

Back to the pressure thingy....

Basic idea.

***Redirecting high pressure internal air downwards in order to enhance lift ..mainly at high speeds.
Admittedly any advantages may be minimal
AS previously stated ; --Admittedly the loose fabric of a normal canopy MAY absorb any lift advantages here .
Not having done any experiments applying this to full size canopies any application to parachutes of this idea has untested results.


As to there being no excess pressure within a ram -air wing ...well Ok... the pressure build up does just keep providing a tighter skin which can potentially have its own lift advantages or if the canopy balloons the changed shape can add its own drag. This is most apparent with older canopy designs with fat trailing edges which get fatter as the speed increases..
This is partly why I referred to the wings fabric absorbing some of the effects of this concept. However at high speeds the extra pressure (past a certain pressure point) could still be diverted downwards giving xtra lift without having to distort the rear of the wing as in with the ‘flaps’.. Simple physics..the downwardly pumped air creating an opposite upward force.ie lift.
Admittedly other effects may reduce the advantages as has been pointed out .

As originally mentioned this could be more applicable to wing-suit designs that incorporate stiffer wing surfaces while still employing ram air principles.
This concept appears to work just fine with a stiffish wing surface.... in my little tests anyway..

My experiments (in a wind-tunnel powered by a leaf-blower ) show some apparent improvements in lift as the tufts indicate some movement as described. If air is moving downwards out of these vents without distorting the airfoil then it seems likely that some xtra lift is being created. Of course for complete validation of this idea more sophisticated tests would be necessary. . Whether these improvements are maintainable during different flight modes or only available at certain speeds and attitudes is still to be determined. You may remember I mentioned this as a form of air flap.

The design simply redirects built up pressure from the ram inlet and front internal portion of the airofoil in a downward direction through the rear or the bottom wing (through micro holes or simpler well placed one-way vents ).

***The idea of having say only the rear 1/3 of the wing airlocked ( behind the vents) is to provide some stability in the rear aerofoil shape as well as giving the wing increased flare power due to the pulled down sections maintaining a ‘better ‘ shape.
It is also proposed that the airlocked ‘flaps’ could use the vent hole locations as a more definite hinge/ pivot point. This could potentially provide a stiffer and less deformable ‘flap’ for flaring purposes as well as more definitely closing the vents during the flare.



**The original idea of redirecting the increased internal pressure achieved during higher speeds forms the basis of a follow on idea where the drag created by the wingtip vortices can be minimised by redirecting internal pressure in way that reduces these vortices. This very well may provide more benefits than my original idea.


This is definitely easier to visualise than describe.

The creation of the wingtip vortices is (apparently) largely due to the remixing of the upper low pressure and lower high pressure air as it passes over and past an aerofoil sectioned wing.
This movement is generally inwards on top of the wing and outwards beneath it (ie HP to LP).
By introducing higher pressure into these vortices at specific locations it is intended to minimise the power of these tip vortices. In particular this idea is applicable to wing-suit design although some canopy advantages could also ensue. More than just an idea and yes I am aware of the winglet designs that already do this.
Using ram air pressure redisribution may be able to achieve some similar effects.
Conservation of energy is a bit of a given isn’t it ?? This is more about redistribution of energy.

The variables in these ideas are many and varied and include such things as inlet design taking into account different flight modes and attitudes ,outlet design and placement, deformable aerofoil concepts (airlocked flaps , possible slotted flaps, pop up slats). Also the basic aerofoil shape is a huge variable as thinning the aerofoil and sharpening the trailing edge often does provide better speed, lift and flight advantages.
However I feel the apparent effects of the original idea of redirecting pressure would still be present .

I’m having fun with the visualising of these ideas and am not so ready to listen to supposedly informed (but unsubstantiated) negative views as the complexity of this collection of ideas encourages me to keep an open mind.
Complicated?? ..yeah OK... at the moment but out of it all it is hoped something more solid and easily defined and who knows even useable may be produced.
That is being creative after all.

Wishful thinking ?? ........do it all the time.


Cheers.

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