Split tank

A solution to reduce sloshing in the tank is to compartmentalize the latter. Indeed, inserting walls into the tank can be a way to counter the sloshing of water or retardant, and consequently it can help to reduce the mechanical stress exerted on the plane. To realize that part of the study, we create a new geometry, including the new walls. Herebelow is a diagram of this new geometry in which we inserted four walls :

            

Compartmentalized tank with four walls (same dimensions of the tank as before)

 

Herebelow are two plots : water level function of time on the left wall and on the fourth inside wall, and fast fourier transform of water level for the same two walls :

We can notice that there is the same frequency on the two walls, but a phase difference appears. Plus, if we compare Fluent's results with the theory, we have :

Analysing this values, we see that the water level elevation is the same with Fluent and in theory. However, it is not the case for frequency and dissipation time. Indeed, Fluent results differs from theory for frequency and dissipation time. This can be due to the fact that the "long waves" hypothesis is no longer valid or to the fact that each part of the tank communicates with the others at the bottom.

Apart from that, the compartmentalized tank solution obviously helps to reduce the sloshing (elevation of water level much less important than before).