Soundwaves Boost Wing Lift

Here's some news that recently came out:

http://www.newscientist.com/article.ns?id=dn7867

http://abc.net.au/science/news/stories/s1439827.htm

Apparently, soundwaves can help airflow stay near the wing and increase
lift. This can help smaller aircraft to avoid stalling at lower
airspeeds. Is this a technology that could be usefully applied to
existing small aircraft? Or would it require some totally new design
thinking?

" wrote in message
ups.com
| Here's some news that recently came out:
|
| http://www.newscientist.com/article.ns?id=dn7867
|
| http://abc.net.au/science/news/stories/s1439827.htm
|
| Apparently, soundwaves can help airflow stay near the wing and
| increase lift. This can help smaller aircraft to avoid stalling at
| lower airspeeds. Is this a technology that could be usefully applied
| to existing small aircraft? Or would it require some totally new
| design thinking?



It would also require heavy metal music.



Well _somebody_ had to say it.


--

Cheers


Dave Kearton

I was thinking perhaps at least drones could benefit from this
technology, since they tend to be smaller and might have to travel at
lower speed to do ground surveillance.

Hmm, or what about at least toy RC hobby aircraft?

Comments?

On Sat, 20 Aug 2005 16:31:43 -0700, wrote
(in article . com):

Here's some news that recently came out:

http://www.newscientist.com/article.ns?id=dn7867

http://abc.net.au/science/news/stories/s1439827.htm

Apparently, soundwaves can help airflow stay near the wing and increase
lift. This can help smaller aircraft to avoid stalling at lower
airspeeds. Is this a technology that could be usefully applied to
existing small aircraft? Or would it require some totally new design
thinking?


I have some of the piezo polymer film they were probably using (from SONAR
experiments, and a steel plate target that tells you where the bullet hit).
The amplitudes would be very small, but covering a wing on an RV or Bonanza
would be less than five pounds in weight, including the high voltage
electrics needed for the piezoelectric material.

But New Scientist is not the most reputable source (called New Age Scientist
by some, ignored by the rest) and I would have to see this confirmed by
another lab. It smells a lot like the kind of signal that screws up your
instrumentation. The drive for the film is likely 800 to 1,200 volts and at
400 Hz running on a little model in a wind tunnel with sensitive detectors of
various sorts. I'll just say I'm skeptical.

-- Charlie Springer

Charlie Springer wrote:
On Sat, 20 Aug 2005 16:31:43 -0700, wrote
(in article . com):


Here's some news that recently came out:

http://www.newscientist.com/article.ns?id=dn7867

http://abc.net.au/science/news/stories/s1439827.htm

Apparently, soundwaves can help airflow stay near the wing and increase
lift. This can help smaller aircraft to avoid stalling at lower
airspeeds. Is this a technology that could be usefully applied to
existing small aircraft? Or would it require some totally new design
thinking?



I have some of the piezo polymer film they were probably using (from SONAR
experiments, and a steel plate target that tells you where the bullet hit).
The amplitudes would be very small, but covering a wing on an RV or Bonanza
would be less than five pounds in weight, including the high voltage
electrics needed for the piezoelectric material.

But New Scientist is not the most reputable source (called New Age Scientist
by some, ignored by the rest) and I would have to see this confirmed by
another lab. It smells a lot like the kind of signal that screws up your
instrumentation. The drive for the film is likely 800 to 1,200 volts and at
400 Hz running on a little model in a wind tunnel with sensitive detectors of
various sorts. I'll just say I'm skeptical.

-- Charlie Springer


No need to be skeptical on this on Charlie. The technique will work.
Unfortunately, the five pounds of high-maintainence, active equipment
can be replaced with a few ounzes of turbulator strips.

I read one of the NASA reports, done YEARS ago, on the Larc website.
They used the same techique, using sound waves to re-energize the
boundary layer. Pointless was their conclusion if I remember correctly.


--
This is by far the hardest lesson about freedom. It goes against
instinct, and morality, to just sit back and watch people make
mistakes. We want to help them, which means control them and their
decisions, but in doing so we actually hurt them (and ourselves)."

In article ,
Ernest Christley wrote:

Charlie Springer wrote:
On Sat, 20 Aug 2005 16:31:43 -0700, wrote
(in article . com):


Here's some news that recently came out:

http://www.newscientist.com/article.ns?id=dn7867

http://abc.net.au/science/news/stories/s1439827.htm

Apparently, soundwaves can help airflow stay near the wing and increase
lift. This can help smaller aircraft to avoid stalling at lower
airspeeds. Is this a technology that could be usefully applied to
existing small aircraft? Or would it require some totally new design
thinking?

I'll just say I'm skeptical.

No need to be skeptical on this on Charlie. The technique will work.
Unfortunately, the five pounds of high-maintainence, active equipment
can be replaced with a few ounzes of turbulator strips.

I read one of the NASA reports, done YEARS ago, on the Larc website.
They used the same techique, using sound waves to re-energize the
boundary layer. Pointless was their conclusion if I remember correctly.

Kinda makes you wonder if they used a particular kind of "noisy" sound
wave, or simple shapes like sine waves.

It'd be really funny if it turned out to work with random or
less-patterned noise, and they missed it because they were too
organized...

--
I don't have a lifestyle.
I have a lifeCSS.

On Sun, 21 Aug 2005 19:22:47 -0700, Chad Irby wrote
(in article ):

Kinda makes you wonder if they used a particular kind of "noisy" sound
wave, or simple shapes like sine waves.

It'd be really funny if it turned out to work with random or
less-patterned noise, and they missed it because they were too
organized...

One would be tempted to think this, but all noise (including triangle and
square waves) can be constructed from a sum of sines and cosines. It is
called Fourier's Theorem, and it works so well nearly all digital signal
processing is based on it to some extent. Note that the researcher's 400 Hz
signal (close to the A flat above middle C) could form some pretty irritating
beats with the engine/propeller. Concert A is 440 and I suspect anybody who
has worked with military aviation is familiar with the sound of the 400 Hz
power systems.

-- Charlie Springer

In article l.net,
Charlie Springer wrote:

On Sun, 21 Aug 2005 19:22:47 -0700, Chad Irby wrote
(in article ):

Kinda makes you wonder if they used a particular kind of "noisy" sound
wave, or simple shapes like sine waves.

It'd be really funny if it turned out to work with random or
less-patterned noise, and they missed it because they were too
organized...

One would be tempted to think this, but all noise (including triangle and
square waves) can be constructed from a sum of sines and cosines.

Technically, yes, but there could be too many situations where "simple"
noise has nothing like the same effect "complex" noise does.

Considering that the airflow across the wings of small aircraft is
generally subsonic, simple versus complex waveforms could make a real
difference (for the generation or prevention of standing waves?).

--
I don't have a lifestyle.
I have a lifeCSS.

In article . com,
" wrote:

Here's some news that recently came out:

http://www.newscientist.com/article.ns?id=dn7867

http://abc.net.au/science/news/stories/s1439827.htm

Apparently, soundwaves can help airflow stay near the wing and increase
lift. This can help smaller aircraft to avoid stalling at lower
airspeeds. Is this a technology that could be usefully applied to
existing small aircraft? Or would it require some totally new design
thinking?

Here's a quote from the article in New Scientist (first reference above):

"In wind tunnel tests, Salmon stuck sections of plastic piezo-electric
film to wing segments. This film vibrates when an electrical signal is
applied, producing sound."

This sure sounds (no pun intended) like aftermarket stuff to me. It
might find its way into production eventually, but it sounds like you
could go stick some tweeters on your Cessna tomorrow and start landing
at 35 knots. That'd raise a few eyebrows among the line judges.

Of course, the best way to avoid stalls is to learn how to fly. No
technology in the world is going to render pilot error obsolete. OK,
I'll make one concession, for wind shear on final. It would be nice to
stay airborne when dropping through the bottom of a 20 knot headwind
layer.

Well, could this technology be used to augment the performance of
canards? We know that aerobody designs that are optimized for
high-speed supersonic flight may unfortunately not be so efficient for
low-speed flight around takeoff and landing. Could this sonic lift
technology be used instead of canards, or maybe to boost the lift from
canards? Then maybe you could have smaller canards at least, although
I'm not sure liability canards pose to begin with. Also I don't know
what you'd do in the event of an unpowered landing.

I was also thinking about how stubby-winged re-entry vehicles like the
old X-15 or even the new SpaceshipOne might benefit from that 20%
increased lift.

What about using this technology for something more exotic, like a
martian aeroplane? With the thinner atmosphere producing less lift,
perhaps this sonic boost might make a crucial difference.