[mxpxer7]

Hello all,

I'm working on a team to design an Air Tanker plane (plane which drops retardant on fires). We're coming into the project half way through so the plane exist but it isn't performing as expected.

Its a gravity fed system with roughly 107" of head, during a drop, the flow rate of the first 1000 gallons of retardant is slow and then speeds up. So in the first 2 seconds the flow rate is slow and then it actually increases, then naturally as we loose head it decreases.

I'm thinking its because it takes time for gravity to act on the the water. However, using Bernoulli's equation thsi time for the fluid to accelerate is not represented... I'm wondering if i'm on the right track with my explanation, and if so, how would i mathematically represent the time for the fluid to accelerate? Any thoughts or opinions are appreciated!