Language: 
To browser these website, it's necessary to store cookies on your computer.
The cookies contain no personal information, they are required for program control.
  the storage of cookies while browsing this website, on Login and Register.

GDPR and DSGVO law

Storing Cookies (See : http://ec.europa.eu/ipg/basics/legal/cookies/index_en.htm ) help us to bring you our services at overunity.com . If you use this website and our services you declare yourself okay with using cookies .More Infos here:
https://overunity.com/5553/privacy-policy/
If you do not agree with storing cookies, please LEAVE this website now. From the 25th of May 2018, every existing user has to accept the GDPR agreement at first login. If a user is unwilling to accept the GDPR, he should email us and request to erase his account. Many thanks for your understanding.
Amazon Warehouse Deals ! Now even more Deep Discounts ! Check out these great prices on slightly used or just opened once only items.I always buy my gadgets via these great Warehouse deals ! Highly recommended ! Many thanks for supporting OverUnity.com this way.

User Menu

A-Ads

MN LiveCoach

Masternodes Live Coaching

Powerbox

Smartbox

3D Solar

3D Solar Panels

DC2DC converter

Micro JouleThief

FireMatch

FireMatch

CCKnife

CCKnife

CCTool

CCTool

Magpi Magazine

Magpi Magazine Free Rasberry Pi Magazine

Battery Recondition

Battery Recondition

Arduino

Ultracaps

YT Subscribe

Gravity Machines

Tesla-Ebook

Magnet Secrets

Lindemann Video

Navigation

Products

Products

WaterMotor kit

Statistics

  • *Total Members: 83458
  • *Latest: Neta160

  • *Total Posts: 512840
  • *Total Topics: 15261
  • *Online Today: 44
  • *Most Online: 103
(December 19, 2006, 11:27:19 PM)
  • *Users: 3
  • *Guests: 13
  • *Total: 16

Author Topic: Directorly Downwind Faster than the Wind  (Read 119797 times)

Offline sterlinga

  • Full Member
  • ***
  • Posts: 235
    • Pure Energy Systems
Directorly Downwind Faster than the Wind
« on: December 07, 2008, 10:58:48 PM »
This one will blow you away.

Is it possible to build a device in which the forward motion turns a wheel that turns a propeller which provides enough wind propulsion to accelerate the device forward faster than the air around it? You would think not, but some investigators appear to have accomplished just that.

http://peswiki.com/index.php/Directory:Directly_Downwind_Faster_than_the_Wind

Plans included.

http://peswiki.com/index.php/Directory:Directly_Downwind_Faster_than_the_Wind#Parts_List

Anyone game to build one quickly and validate?

Sterling

Free Energy | searching for free energy and discussing free energy


Offline TechStuf

  • Hero Member
  • *****
  • Posts: 1280
    • Biblical Record Proves True
Re: Directorly Downwind Faster than the Wind
« Reply #1 on: December 08, 2008, 02:41:20 AM »

Interesting....


Now, how about travelling 64% of current windspeed.


Directly against such wind.


http://www.sciencedaily.com/releases/2008/08/080827104702.htm


I'd bet I can count on one hand the number of years ago that many "lettered men" would have scoffed at such a preposterous proposition.



Regards,



TS

Offline sterlinga

  • Full Member
  • ***
  • Posts: 235
    • Pure Energy Systems
Re: Directorly Downwind Faster than the Wind
« Reply #2 on: December 08, 2008, 04:18:15 AM »
I talked with Spork33 today, after posting the above.  He's the person featured in several of the DDFTTW videos.

He is convinced that existing laws of aerodynamics can explain this phenomena, and he is in process of composing a scientific paper for publication in a refereed journal that will detail the mechanics involved.

Bear in mind that you will not be able to just plop this on a flat surface such as a gym floor, give it a good push, and it take off accelerating. The device on the treadmill is analogous to a cart going along with a tail wind of the same speed, and the mechanism makes it go faster than the tail wind.
He said he has been assembling about 20 of these to ship out to a few people (primarily skeptics) from various forums who have asked to replicate the effect. He said that in doing several at once, the parts run around $40.00 USD. He asks another $5.00 for shipping. So at this juncture he's only doing it on a limited basis for scientific advancement. At that price, he's not willing to make very many.

Until the thing is mass produced, it will be fairly expensive. We (PES Network, Inc.) are in discussion with him about entering into an agreement to build and ship kits with adequate mark-up to make it worth our while, e.g. $80 retail. If you are interested (customer side or business side), please send an email to DDWFTTW.kit@pureenergysystems.com .

Because the gadget won't accelerate across a flat surface but will only move forward on a treadmill, the number of people wanting one will probably be fairly low, and the practical aspects perhaps lower yet.

It certainly is a scientific curiosity. Perhaps the principles underlying it may eventually spur some significant aerodynamic advancements in efficiency.

Free Energy | searching for free energy and discussing free energy

Re: Directorly Downwind Faster than the Wind
« Reply #2 on: December 08, 2008, 04:18:15 AM »
Sponsored links:




Offline Mr.Entropy

  • Full Member
  • ***
  • Posts: 195
Re: Directorly Downwind Faster than the Wind
« Reply #3 on: December 08, 2008, 04:27:03 AM »
It's counter-intuitive, but physics is OK with this device.  This possibility has been discussed at length on Steorn here:

http://www.steorn.com/forum/comments.php?DiscussionID=60059&page=5&Focus=2265999

My contribution:

Given access to two streams with parallel velocities (relative to you) Va and Vb, apply net force Fa to the first and Fb to the second.

your acceleration is determined by the net reaction force -(Fa+Fb):

No matter what those relative velocities are, as long as they're different you can acheive any net acceleration force F without expending energy by setting:

Fa = F*Vb/(Va-Vb)
Fb = F*Va/(Vb-Va)

Calculate power expenditure using P=F.v:

P = Fa*Va + Fb*Vb
= F*Va*Vb/(Va-Vb) + F*Va*Vb/(Vb-Va)
= F*Va*Vb/(Va-Vb) - F*Va*Vb/(Va-Vb)
= 0

Check net reaction force

-(Fa + Fb)
= - ( F*Vb/(Va-Vb) + F*Va/(Vb-Va) )
= - ( F*(Vb-Va)/(Va-Vb) )
= F

Free Energy | searching for free energy and discussing free energy


Offline Goat

  • Hero Member
  • *****
  • Posts: 619
Re: Directorly Downwind Faster than the Wind
« Reply #4 on: December 08, 2008, 06:25:02 AM »
@ All

Does this theory mean that we could apply it to a windmill in reverse to get more energy out of the wind ?

Regards,
Paul

Free Energy | searching for free energy and discussing free energy

Re: Directorly Downwind Faster than the Wind
« Reply #4 on: December 08, 2008, 06:25:02 AM »
Sponsored links:




Offline nightlife

  • Hero Member
  • *****
  • Posts: 1080
Re: Directorly Downwind Faster than the Wind
« Reply #5 on: December 08, 2008, 08:37:25 PM »
Goat, "Does this theory mean that we could apply it to a windmill in reverse to get more energy out of the wind ?"

 I would think that they have already tested both and they are nor designed to work off what is best but you never know, it may have been over looked.

 I dont have a wind mill to test but if some one else does, please check this out and see and then let us know.

Offline hartiberlin

  • Administrator
  • Hero Member
  • *****
  • Posts: 7931
    • free energy research OverUnity.com
Re: Directorly Downwind Faster than the Wind
« Reply #6 on: December 08, 2008, 08:57:04 PM »
It's counter-intuitive, but physics is OK with this device.  This possibility has been discussed at length on Steorn here:

http://www.steorn.com/forum/comments.php?DiscussionID=60059&page=5&Focus=2265999

My contribution:

Given access to two streams with parallel velocities (relative to you)

What 2 streams do you exactly mean ?
Can you explain it some more ?

It seems from the videos, that it only depends how fast the wheels
are rotating and this is geared up to the propeller.

So from the test videos on the threadmill
it seems, that this device only needs to be pushed up to 10 miles/hour speed
and then it will accelerate itsself without needing any blowing wind itsself to speed up.
All is probably done via the right combination of the right wheel to propeller gear ratio.

Then it seems to overcome friction and seems to selfaccelerate.

So it seems one could build cars like this, that just only
need a motor to push them over the 10 miles/hour threshold
and then you could switch off the motor and the car would
selfaccelerate. Amazing !

Regards, Stefan.

Free Energy | searching for free energy and discussing free energy

Re: Directorly Downwind Faster than the Wind
« Reply #6 on: December 08, 2008, 08:57:04 PM »
Sponsored links:




Offline Mr.Entropy

  • Full Member
  • ***
  • Posts: 195
Re: Directorly Downwind Faster than the Wind
« Reply #7 on: December 09, 2008, 12:27:11 AM »
What 2 streams do you exactly mean ?
Can you explain it some more ?
The original thread at steorn was about sailing.
In this case, the 'streams' are the treadmill and the air at rest.  Or the moving wind and the road at rest.
Quote
It seems from the videos, that it only depends how fast the wheels
are rotating and this is geared up to the propeller.
The air and road have to be moving at different speeds.
Quote
So it seems one could build cars like this, that just only
need a motor to push them over the 10 miles/hour threshold
and then you could switch off the motor and the car would
selfaccelerate. Amazing !
Sure.  They'd still be wind powered, though, so you'd have to keep them very light, and the speed at which you could practically expect to move is very limited.

Offline TechStuf

  • Hero Member
  • *****
  • Posts: 1280
    • Biblical Record Proves True
Re: Directorly Downwind Faster than the Wind
« Reply #8 on: December 09, 2008, 01:07:02 AM »

Even a propellor with zero pitch, once started, should continue turning, as the 'virtual surface area' is increased with velocity.  The fact that the prop still works when pitched to provide a modicum of thrust against the tail wind, demonstrates how effective a small surface area can be at creating said increase in 'virtual surface area' when moving perpendicular to the flow of wind.

This still does not fully account for the slight force asymmetry expressed in the higher vehicle velocity, which is why I propose duplicating the experiment with winglets on the prop tips.

It seems plausible that VRS (vortex ring state) may be involved....producing a small area of low pressure ahead of the craft.  If such is the case, winglets of sufficient size at the prop tips will serve to modify velocity differentials.

TS


Free Energy | searching for free energy and discussing free energy

Re: Directorly Downwind Faster than the Wind
« Reply #8 on: December 09, 2008, 01:07:02 AM »
3D Solar Panels

Offline Pirate88179

  • elite_member
  • Hero Member
  • ******
  • Posts: 8368
Re: Directorly Downwind Faster than the Wind
« Reply #9 on: December 09, 2008, 01:24:35 AM »
@ All:

My main concern is that the fellow said you can't just put this on a flat surface like a gym floor and have it work..it works on the treadmill.  This I do not understand.  When learning to fly and also building my own small airboat, I had a chance to learn a little about propellers.  The main principle I see here is that when a propeller is turning, the relative wind sees it as a solid disk.  Now, this only applies when the prop, depending on the pitch and airfoil design, is turning faster than the relative wind, or slower.  There is an equilibrium point for all propellers at a certain rpm in a certain relative wind that adds 0 drag and 0 thrust, but this is a small window.  They use this when they teach you to land simulating an "engine out" experience.  If you just set the engine to idle, the drag produced by the prop would be way higher than in a real engine out scenario, and therefore would be of little use for learning to deal with a real one.

So, I can see where you have a 10 mph tailwind, and the prop is turning via the wheels after an initial push, so the prop then acts as a parachute or sail to catch the tailwind and push the craft faster.  Once it reaches the speed of the tailwind, as Stefan said, through proper gear ratios, the propeller turns at its designed rpm and therefore produces thrust which makes it go faster than the wind.  All of this works for me with what I know except it not running on a flat surface like a gym floor.  This part, I can not explain at all.

Bill

Offline Yucca

  • Hero Member
  • *****
  • Posts: 884
Re: Directorly Downwind Faster than the Wind
« Reply #10 on: December 09, 2008, 03:24:22 AM »
@ All:

My main concern is that the fellow said you can't just put this on a flat surface like a gym floor and have it work..it works on the treadmill.  This I do not understand.  When learning to fly and also building my own small airboat, I had a chance to learn a little about propellers.  The main principle I see here is that when a propeller is turning, the relative wind sees it as a solid disk.  Now, this only applies when the prop, depending on the pitch and airfoil design, is turning faster than the relative wind, or slower.  There is an equilibrium point for all propellers at a certain rpm in a certain relative wind that adds 0 drag and 0 thrust, but this is a small window.  They use this when they teach you to land simulating an "engine out" experience.  If you just set the engine to idle, the drag produced by the prop would be way higher than in a real engine out scenario, and therefore would be of little use for learning to deal with a real one.

So, I can see where you have a 10 mph tailwind, and the prop is turning via the wheels after an initial push, so the prop then acts as a parachute or sail to catch the tailwind and push the craft faster.  Once it reaches the speed of the tailwind, as Stefan said, through proper gear ratios, the propeller turns at its designed rpm and therefore produces thrust which makes it go faster than the wind.  All of this works for me with what I know except it not running on a flat surface like a gym floor.  This part, I can not explain at all.

Bill

Hi Bill,

The whole things a bit of a mind bender. It´s an impressive device and appears to do something that many people say is impossible which is always a good thing to do!

The only thing I can think of is that on the treadmill, the craft does not see an oncoming airstream and thus sees no air friction. Wheras if you push it along a gym floor it would have to overcome the oncoming air resistance.

Also, I think this craft enables one to move a certain percentage faster than the driving wind, that percentage might vary and have a sweet spot of wind speed where you get the best gain, but in the case of 0mph wind as in a gym then that percentage will be zero so it wont sustain motion. To simulate the gym floor using the treadmill one would have to face the treadmill into a wind that matched the treadmill speed.

P.S.
impressed that you built an airboat! model planes and helis are as far as I´ve gone.

Yucca.

Free Energy | searching for free energy and discussing free energy

Re: Directorly Downwind Faster than the Wind
« Reply #10 on: December 09, 2008, 03:24:22 AM »
3D Solar Panels

Offline allcanadian

  • Hero Member
  • *****
  • Posts: 1317
Re: Directorly Downwind Faster than the Wind
« Reply #11 on: December 09, 2008, 04:29:56 AM »
I thought this was pretty easy to figure out, on the treadmill the device produces near balanced forces, that is thrust nearly equals drag from the driving components or ground speed nearly equals generated air speed. But if this device is travelling with the wind behind it something really neat happens. To understand this I think you have to concentrate on relative motion and the neutral point of force. If the tail wind speed is 5mph pushing the craft forward then when the craft reaches 5mph ground speed the apparent wind you would "feel" is now zero mph so there is very little air resistance. Also if the ground speed is 5mph or equal to the tail wind speed then directly behind the prop there is a point of zero windspeed which constitutes a pressure boundary.
(Wind) 5mph----->zero<-----5mph(propeller)
One analogy could be standing in an elevator moving upwards at 5mph and jumping upwards at 2mph, you "feel" a 2mph velocity(apparent) but you are moving upwards at 7mph(reality). The reason this can happen is because you are "in an elevator", if you were not in an elevator you would have nothing to push against to jump. We can say that the only reason this craft can exceed the wind speed is because the prop generated wind has something to push against and this something is a wall of "pressure" having an apparent velocity of zero mph but having a real ground speed equal to the craft. A good analogy is having the launch pad of a rocket accelerating behind the rocket but not being attached to it, in this case we are not dealing strictly with reactive mass, we are dealing with a wall of pressure acting in the same direction of acceleration because the gasses ejected from the rocket are pushing against a boundary or obstruction. In this device the forces would look something like this--
(wind) 5mph----->Zero<----------- 7mph(propeller)----->2mph 
Total =  (wind) 5mph---> + 2mph----> = 7mph ground speed = 7 mph thrust
As the ground speed increases so does the thrust generated by the propeller but the propeller does not "push" the craft----the pressure generated behind the craft does and the wind has provided half of the velocity to maintain this pressure wall behind the craft and all of the energy to maintain the velocity of the craft.
Regards
AC


« Last Edit: December 09, 2008, 11:14:05 PM by allcanadian »

Offline TechStuf

  • Hero Member
  • *****
  • Posts: 1280
    • Biblical Record Proves True
Re: Directorly Downwind Faster than the Wind
« Reply #12 on: December 09, 2008, 05:34:29 AM »

I wonder what would happen if you put magnets on that thar perpeller.


lol?
« Last Edit: December 09, 2008, 07:13:05 AM by TechStuf »

Offline petersone

  • Full Member
  • ***
  • Posts: 209
Re: Directorly Downwind Faster than the Wind
« Reply #13 on: December 09, 2008, 10:39:31 AM »
Hi all
Do's this mean an electric motor uses less juice when a fan is fixed to the shaft?
peter

Offline PhiScience

  • Jr. Member
  • **
  • Posts: 86
Re: Directorly Downwind Faster than the Wind
« Reply #14 on: December 09, 2008, 03:34:44 PM »
Hi all

 The principle of this device is very simple and straightforward, the “air car” is getting its energy from the treadmill motor. Friction between the wheels and belt turn a shaft that is attached to an angle miter gear that is attached to a second shaft that drives a propeller, thus producing thrust.
At the proper rpm the propeller will produce enough thrust to overcome the friction gravity, and drag to move the vehicle forward. But it is not producing its own energy it is getting it from the treadmill.

Cool toy though.   

 

OneLink