FALCON_12 wrote:Hello,
I would like to conduct a survey regarding your intuition regarding a question.
The simple idea:
instead of turning a thin propeller, I push back a solid disc which opposes the wind much more!In the following diagram, visible here:
,
we see a wind turbine which
sweeps a surface S and a vector V0 perpendicular to S, this is the wind.
On the right, a disk D with the same surface S but
full is represented. This disk is like the wind turbine opposed to the wind.
Let us assume that the wind turbine produces each duration T, an energy E1.
Let us also admit that for the same duration T the disk pushed by the wind moves backwards
at speed V1 over a length d and we can recover the energy that the work of the force F which
grows product. This work, therefore this energy, is worth E2=dF
Without doing any calculations Which of E1 or E2 do you think is greater?
Here are some screenshots of trailed wind turbines that really interested me some time ago.
The author, Pascal Ha Pham, if I'm not mistaken, tried different ways
to extract energy from the wind by opposing it with a surface which recedes in front of it and provides work.
At the time, doing this seemed to me, like all the contributors here except one (if it were that simple!)
spontaneously (or “intuitively”) thought it to be the most efficient way to harvest wind energy
and I had thought of another form of mechanics that could do this.
However, before I started making it, a little voice told me “first estimate the yield of the thing!” ...
Judging that this would be an interesting exercise in mechanics involving some pretty mathematics and
modeling a real phenomenon (which I really like doing) I did the calculations.
Having done so, I therefore gave up working on my system since the maximum yield is disappointing. The wind turbine
conventional, for reasons that I am painfully learning to imagine, and to my total amazement, does better.
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