Microgravity interface velocity

As illustrated in Figure 14.2b, the velocity profile for Region 2 in microgravity is assumed to be a fully developed parabolic profile, similar to the profile for Region 2 in the 1-g case. However, in the microgravity model, the average velocity value is the interface velocity, and not the exit velocity ... 

As shown in Figure 14.5, the normalized interface velocity rapidly decays as the LAD is exposed to vapor. With an interface velocity profile, ullage bubble growth model, cryogenic bubble point model, and analytical flow model, the velocity and pressure fields inside the LAD can be determined in microgravity. The velocity can also be visualized as a function of time as the tank is drained. 

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