Talk:Light Laminar Lifter
From Wise Nano
If your payload is ~100 kg and sheet weight is 7% thats 7 kg. At 7 grams per meter you must have 1,000 square meters of LLL, doable but kind of big. But if its for flying nano-tech products I can see it being really useful.
How resistant would a LLL be to dirt and moisture?
Power source? Heat dissipation? by 4.229.117.36 13:09, 16 Oct 2004 (CDT)
10 m/s airspeed. Given that at least some of the air is going to flow around the lifter, and that the air going through the lifter will not be perfectly coupled to it, assume that the belts must travel at 15 m/s.
Given the posited dimensions, the total belt area is about five times the frontal area of the lifter. And it is subject to atmospheric pressure, which must be resisted by bearing supports.
One square meter of lifter, then, has bearings supporting a total load of aproximately 500,000 newtons. Assume that the bearings are REALLY good, with a coefficient of friction of approximately 0.1%. Power consumption due to friction in the slats will then be 0.001*500,000*15, or about 7.5 kilowatts per square meter. Not TOO bad, I guess. Certainly doable with the sorts of mechanisms described in Nanosystems.
Assume these frictional losses are made up by a 90% efficient motor/drive train, powered by a 50% efficient rectenna, (No need to find someplace to hide the fuel.) then neglecting the work required to overcome the difference in air pressure between the top and bottom of the lifter, total power consumption is about 17 KW per square meter. All this power must be gotten rid of as waste heat somehow, presumably by rejecting it to the air flow.
Ten cubic meters of air, approximately 10 kg, must accomidate 17 JK of energy. Now, the specific heat of air is pretty close to one Kj/Kg degree Kelvin, so the airflow would have to increase in temperature by only 1.7 degrees Kelvin, or about 3.6 degrees F. So heat dissipation is evidently not a problem.
I'd say the lifter is feasible, though one might quibble with some of the design details.
