Aesquire
Well-Known Member
A now closed thread on Jetstream balloon solar buzzword flight raised a question.
The complexity of the proposal caught some flack, but there was a claim/promise that caught my attention, that kites/sails/etc. might be used to get energy from the wind, from a balloon.
My initial thought was sticking a wind generator on a free flight balloon is silly, as there's near zero relative wind.
But the atmosphere isn't uniform in flow. Dynamic soaring using the wind gradient from ground friction is done by seagulls and RC models & has been experimented with by manned gliders
So my thoughts went to possible ways to tap wind gradients in flight, from a balloon.
I'm not sure the type of balloon matters as long as you have altitude control, so for my example I'll assume a regular Raven hot air balloon available today.
If you go up and down you get a relative wind to tap, but that obviously has severe limits on lifting gas or propane capacity and unfortunately physics won't let you make out on that process. ( you can't get enough power to make heat or electrolysis to make hydrogen etc. to sustain flight)
Perpetual motion isn't the goal, you are going to come down when your fuel or ballast runs out. Gravity sucks.
But if you can tap a different flow of air at a distance? You could fly ( for example) over a wind sheer or jet stream and lower a wind generator into a flow with a different vector and tap that.
And I have some ideas involving kites, which are being used today for ground/water based propulsion and experimental power generation. ( kites reeling out cable and being pulled back in low drag mode )
I'm not assuming or promising any practical use, but am curious about potential methods for using the air currents from a free flight balloon.
Charging batteries for radios or advertising lights, might be a useful goal, but what you do with the energy isn't the question, it's can you tap it in the first place?
I'm open to suggestions and observations. I'm well aware that nothing practical is likely, but as a logic and physics puzzle it's interesting.
The complexity of the proposal caught some flack, but there was a claim/promise that caught my attention, that kites/sails/etc. might be used to get energy from the wind, from a balloon.
My initial thought was sticking a wind generator on a free flight balloon is silly, as there's near zero relative wind.
But the atmosphere isn't uniform in flow. Dynamic soaring using the wind gradient from ground friction is done by seagulls and RC models & has been experimented with by manned gliders
So my thoughts went to possible ways to tap wind gradients in flight, from a balloon.
I'm not sure the type of balloon matters as long as you have altitude control, so for my example I'll assume a regular Raven hot air balloon available today.
If you go up and down you get a relative wind to tap, but that obviously has severe limits on lifting gas or propane capacity and unfortunately physics won't let you make out on that process. ( you can't get enough power to make heat or electrolysis to make hydrogen etc. to sustain flight)
Perpetual motion isn't the goal, you are going to come down when your fuel or ballast runs out. Gravity sucks.
But if you can tap a different flow of air at a distance? You could fly ( for example) over a wind sheer or jet stream and lower a wind generator into a flow with a different vector and tap that.
And I have some ideas involving kites, which are being used today for ground/water based propulsion and experimental power generation. ( kites reeling out cable and being pulled back in low drag mode )
I'm not assuming or promising any practical use, but am curious about potential methods for using the air currents from a free flight balloon.
Charging batteries for radios or advertising lights, might be a useful goal, but what you do with the energy isn't the question, it's can you tap it in the first place?
I'm open to suggestions and observations. I'm well aware that nothing practical is likely, but as a logic and physics puzzle it's interesting.
