Tinman
Think about what you just said,
"Every time the blades rotate just a bit, there surfaces are now moving into an area of the wind that has not yet impacted the blades".
That is true when the cart is below the wind speed but when the cart speed is equal to the wind speed... there is no wind. Thus there is nothing to impact the blades. Which is the reason why no drag based device can exceed the wind speed.
In fact it relates to a simple experiment anyone can do. Grab a stick and tie a piece of flexible yarn or string on it then jump in your truck and drive directly down wind with the stick out the window. When the yarn falls straight down your speedometer reading is the current wind speed. This proves that when our velocity directly down wind is equal to the wind speed there is in fact no wind.
So you seem to be barking up the wrong tree in my opinion.
AC
As I said, it is hard for most to understand, as they see the blades (sails) as being stationary, when in fact, they are rotating.
The angle and rotation of the blades means they are in effect being continually impacted by an area of the wind not yet stopped by the blades.
I will try and explain in a way that is easily understood.
Take a big long tub of butter (our wind). Now, you get a propeller, say from a boat engine.
You move the tub of butter down the road at say 10mph. You then rotate the propeller when submerged in the butter, so as it moves forward in the same direction the tub of butter is going down the road.
The propeller will now move forward down the road at a higher rate of speed than the tub of butter is going, due to the fact that the blades of the propeller are cutting into a new portion of the moving butter as it rotates. As every action has an equal and opposite reaction, the new portion of butter that continuously impacts the blades surface, is pushing on the blades just as much as the blades are pushing on the butter.
So, the wind is just a less dense fluid than the butter, but it still has the same working principle.
It does not matter that the wind is going slower than the vehicle, as the propeller blades will be continuously impacting a new portion of the wind that will push against the propeller blades.
To sum up
1- the vehicle is stationary
2-the wind pushes against the blades of the propeller
3-the vehicle starts to move
4- the moving vehicle then causes the propeller to rotate
5- the rotating propeller ensures that the blades are continually impaction a new portion of the wind
6- the wind is always pushing against the propeller, regardless of the fact that the vehicle itself is going faster than the wind, due to the angle of the blades, and their rotation into the new portion of the wind.
In effect, the blades surfaces (sails) are moving down wind slower than the wind, regardless of the fact that the vehicle is moving down wind faster than the wind.
The simple fact is, if the wind stops, so does the vehicle.
The vehicle does not make it's own wind to push against.
Brad
Never let your schooling get in the way of your education.
feature is available which provides a place all members can chat, either publicly or privately.
Author
Topic: Blackbird and the secrets it holds. (Read 7456 times)
