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Author Topic: does the shape of a hot air balloon make a difference to speed?  (Read 2024 times)

Offline annie123

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My son insists that the shape of a balloon has none or very little effect on its performance in wind currents. I would have thought that odd shapes with protuberances as in many of the balloons at the hot air festival here right now would affect their speed because of varied resistance. Any hot air balloon experts out there?


 

Offline CliffordK

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The hot air balloons more or less travel with the wind.  So, an odd shape should not slow it down, and anything that would increase the wind resistance might actually be beneficial.

Weight, of course would also be an issue.  a tear-dropped bag would likely minimize the weight of the material vs the amount of contained air.  As well as maximizing the heat distribution within the balloon and minimizing surface area cooling.  This likely would not make a huge difference, but might mean additional fuel would be required on some of the odd shaped balloons.

The weight in turn might affect the performance in the air, but it is likely minimal.
 

Offline yor_on

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A balloon made as a sail Clifford? Would that speed it up? And could one make a shape that allowed it to move closer to the wind?
=

No it wouldn't matter, would it :)
It would be mass relative its area meeting the wind wouldn't it?
Thought of a sailing boat there, but that's a different beast.
« Last Edit: 04/09/2012 04:19:15 by yor_on »
 

Offline CliffordK

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St. Louis has an annual balloon race.

And, some sponsors have unique shaped balloons.  Hopefully I won't get banned for allowing the post of adversing logos...  Should I invert them like BBC?



And Yes, yor_on, somebody apparently designed a sailing ship balloon.


While the mass would be greater for the odd shaped balloons, the surface area may be proportionally greater, so the two may compensate for each other.
« Last Edit: 04/09/2012 05:14:08 by CliffordK »
 

Offline yor_on

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That one was really cool Clifford :)
 

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