math for energy consumption

[wuzamarine]

I am trying to understand the math/mechanics behind efficiency (not so much performance)
I have a little hubsan X4 that comes a 380mah, 3.7 volt, 4wh battery (I do not have the c rating) that runs for 5 min before it teeters out
I purchased some replacement tri blade props and the flight time reduced to 30 secs.
I would like to understand everything that errored here (for someone looking for efficiency). I would of thought that the additional prop would provide more lift and as long as I was not doing tricks, I could expect additional flight time.
This hypothesis was quickly proven very incorrect.

Is there a formula calculating weight to blade area efficiency requirements?
Where can someone look to to get a very good understanding of the mechanics of prop efficiency?

[Kilrah]

It's WAY more complicated than that. Even 2 2-bladed props can have an extremely different efficiency from their design.

But in general it's assumed that given comparable blade design the more blades the less efficiency, becasue there is less time for the turbulence of one blade to dissipate before the next one hits it.