Rate of Helium Leak

In order to create a report there has to be some investigation. The report will be based upon the observations and calculations therefrom.

i am doing a report on the feasiblity of aerial wind turbines vs. ground based. And since i don't have access to the materials needed to build a mylar ballon large enough to lift a decent size wind turbine into the air, i have researched a formula which will calculate how much helium will be needed to do this. So if i can get a formula which will generally give the rate of helium leak out of a mylar ballon i can calculate the extended costs involved with launching a helium filled mylar ballon carring a wind turbine.

If the balloon is tethered to the ground then it may be possible to replenish the helium at intervals from a cylinder at ground level along a hose attached to the tether, replacing the cylinder upon its getting empty. The balloon would then stay up indefinitely. The costs of replenishing the helium are then only related to the transport of the full and empty cylinders, and the value of a full cylinder charge of helium.

Please publish the report when complete.

That could be the subject of your report. Storm

There are simply too many variables involved to predict the leak rate with any sort of certainty; the "SWAG" is probably as close as one could get. Consistency of the material, construction/configuration of the bladder/fill system, seams, temperatures, pressures, and so on are only some of the variables to consider. It is interesting to note that Mylar toy balloons hold helium much longer than those made of rubber.

Your best bet would be to make an experimental system and acquire some data. Your paper is, after all, an opportunity and/or a requirement to learn something. Doing experiments will be of greater benefit than simply regurgitating someone else's work.

Good luck.