This very cool. Looks like it's using the same principal as a car engine which converts the linear momentum of the pistons to circular/angular momentum. The bigger the propeller the more energy you can harness. Theoretically the bigger your propeller the faster you can go.
Over 2x would be awesome, and another mind boggler. I'm now wondering whether more props on the same axle, like 10 ft apart, might help efficiency. Or even 2 props in the same axis, not axle, geared differently. Not real reason to want o try it, just curious if it could help.
Finally, beyond your already proven proof of concept, I'd love to see a setup that is lower to the ground, with bicycle assist for traffic. HPV builders have been given a huge boost of inspiration, I'm sure!
Congrats! but I was convinced of DDWFTTW & Directly Up Wind devices long ago by math, thought experiments , models & DWFTTW landsailers. DUW works because airfoils produce far more lift than drag. Let's assist human powered vehicles. It's already easy to pedal DW. I'd prefer a small DUW device on a bike to supply (or partly supply) the power to propel a bike DUW. DUW uses a windmill in place of the DDWFTTW prop. The stronger a headwind blows, the better a well designed DUW device works !
One should not confuse DDWFTTW with DUW. Even if the camera guy says "upwind" he means "up APPARENT-wind". Carts that go "up TRUE-wind" use a turbine(windmill) that drives the wheels. This cart ALWAYS uses a propeller driven by the wheels, even when going DDWFTTW and therefore "up APPARENT-wind".
This mechanical analogy shows the difference between DDWFTTW & DUW: watch?v=za_rPKSwiyc
I did mention that DUW requires a windmill & DDWFTTW requires a prop, so I'm not confused. Congratulations again. Its's right for an academic institution to demonstrate DDWFTTW given the controversy, counterintuitiveness and glory for achieving what appears to be miraculous. DDWFTTW props are fairly conventional. DUW requires a different windmill than that of a stationary HAWT in which adverse lift is of no concern. I'm hoping for progress DUW that can have immediate practical applications.
I just had this epiphany as well. A recumbent style, wide and stable skelter could have a collapisble, or even multiple props ON TOP of the human power already making for handy commuting. No wind? Bike lane. Wind? Highway.
Then add solar panels, and my favorite : chiney style airfoil wings for the cyclist(s) to seat inside (pretty aero), with a telescoping upper section to get optinal side wind coverage. No side wind? Wings down to slippery mode, and on the props! NuVinci CVT bike hub for props.
That would be required if the claim were going against the wind. Here, the claim is faster than the wind, in the same direction. Catching up with hot air balloons, so to say. Or am I getting it wrong? I could well be.
No. The teltales indicate some of the windflow around the cart.
They are too close to the device to indicate the apparent wind - which is why they are (I think) pointing upwind when the cart stops at the end.
The airflow induced by the propeller is giving the illusion that the vehicle is exceeding the windspeed when it isnt -or if it is then thats due to the real windspeed dropping.
madtom1999: "The airflow induced by the propeller is giving the illusion that the vehicle is exceeding the windspeed when it isnt"
The teltales are far enough away not to be significantly affected by the wake of the prop. If they where closer you would see some turbulent and circular flow indicated, but they are showing straight back:
watch?v=aDzWh9J1dk4#t=1m23s
The teltales are just an visual indicator. The real evidence will come from measuring wind speed and cart speed.
The telltales show the apparent wind, not the true wind. The true wind is always left to right, and the cart goes directly downwind. The direction of the telltales changes depending on weather the cart goes slower then the wind, or faster than the wind.
After the smashing success of the last two days, we're convinced we can hit over 3x with a few mods. we originally hoped to get to 2x, but that doesn't seem very hard any more. :-)
Look to see this in the next mad max movie
hassleoffa 1 year ago
This very cool. Looks like it's using the same principal as a car engine which converts the linear momentum of the pistons to circular/angular momentum. The bigger the propeller the more energy you can harness. Theoretically the bigger your propeller the faster you can go.
Nomoreidsleft 1 year ago
Wind shear, yes???
scandalxk 1 year ago
@scandalxk
No, the vehicle is not taking advantage of shear -- it's simply slowing down the wind and using the extracted energy to propel itself.
TraderTurok 1 year ago
Over 2x would be awesome, and another mind boggler. I'm now wondering whether more props on the same axle, like 10 ft apart, might help efficiency. Or even 2 props in the same axis, not axle, geared differently. Not real reason to want o try it, just curious if it could help.
Finally, beyond your already proven proof of concept, I'd love to see a setup that is lower to the ground, with bicycle assist for traffic. HPV builders have been given a huge boost of inspiration, I'm sure!
Cloxxki 1 year ago
Congrats! but I was convinced of DDWFTTW & Directly Up Wind devices long ago by math, thought experiments , models & DWFTTW landsailers. DUW works because airfoils produce far more lift than drag. Let's assist human powered vehicles. It's already easy to pedal DW. I'd prefer a small DUW device on a bike to supply (or partly supply) the power to propel a bike DUW. DUW uses a windmill in place of the DDWFTTW prop. The stronger a headwind blows, the better a well designed DUW device works !
Dennbecr 1 year ago
@Dennbecr
One should not confuse DDWFTTW with DUW. Even if the camera guy says "upwind" he means "up APPARENT-wind". Carts that go "up TRUE-wind" use a turbine(windmill) that drives the wheels. This cart ALWAYS uses a propeller driven by the wheels, even when going DDWFTTW and therefore "up APPARENT-wind".
This mechanical analogy shows the difference between DDWFTTW & DUW: watch?v=za_rPKSwiyc
eyytee 1 year ago
I did mention that DUW requires a windmill & DDWFTTW requires a prop, so I'm not confused. Congratulations again. Its's right for an academic institution to demonstrate DDWFTTW given the controversy, counterintuitiveness and glory for achieving what appears to be miraculous. DDWFTTW props are fairly conventional. DUW requires a different windmill than that of a stationary HAWT in which adverse lift is of no concern. I'm hoping for progress DUW that can have immediate practical applications.
Dennbecr 1 year ago
I just had this epiphany as well. A recumbent style, wide and stable skelter could have a collapisble, or even multiple props ON TOP of the human power already making for handy commuting. No wind? Bike lane. Wind? Highway.
Then add solar panels, and my favorite : chiney style airfoil wings for the cyclist(s) to seat inside (pretty aero), with a telescoping upper section to get optinal side wind coverage. No side wind? Wings down to slippery mode, and on the props! NuVinci CVT bike hub for props.
Cloxxki 1 year ago
Instead of tell-tales on the vehicle go and put a line of tell-tales along your course.
darktokolosh 1 year ago
You rather need exact anemometers along the course.
eyytee 1 year ago
That would be required if the claim were going against the wind. Here, the claim is faster than the wind, in the same direction. Catching up with hot air balloons, so to say. Or am I getting it wrong? I could well be.
Cloxxki 1 year ago
No. The teltales indicate some of the windflow around the cart.
They are too close to the device to indicate the apparent wind - which is why they are (I think) pointing upwind when the cart stops at the end.
The airflow induced by the propeller is giving the illusion that the vehicle is exceeding the windspeed when it isnt -or if it is then thats due to the real windspeed dropping.
madtom1999 1 year ago
madtom1999: "The airflow induced by the propeller is giving the illusion that the vehicle is exceeding the windspeed when it isnt"
The teltales are far enough away not to be significantly affected by the wake of the prop. If they where closer you would see some turbulent and circular flow indicated, but they are showing straight back:
watch?v=aDzWh9J1dk4#t=1m23s
The teltales are just an visual indicator. The real evidence will come from measuring wind speed and cart speed.
eyytee 1 year ago
Bad Luck!
Looking at the telltales at the end of the run it would appear that the wind turned 180 during the run. Not such a success after all.
madtom1999 1 year ago
The telltales show the apparent wind, not the true wind. The true wind is always left to right, and the cart goes directly downwind. The direction of the telltales changes depending on weather the cart goes slower then the wind, or faster than the wind.
eyytee 1 year ago
Comment removed
Dennbecr 1 year ago
Very nice run. Congratulations!
It'll be very interesting to see what max speed ratio you'll get. What do you think? Any betting going on yet?
Cygnus65 1 year ago
@Cygnus65
After the smashing success of the last two days, we're convinced we can hit over 3x with a few mods. we originally hoped to get to 2x, but that doesn't seem very hard any more. :-)
TraderTurok 1 year ago