Tetra CFD Applications
Stage Separation
A missile stage separation
event occurs when the booster motor separates from the upper stage vehicle components. Active stage
separation involves the firing of the upper stage motor to initiate separation, and this significant
flight event can be effectively modeled using CFD. In most cases, stage separation is treated as
quasi-steady so that the relative motion of the two bodies is decoupled from the fluid dynamics (this is
a valid assumption if the fluid dynamic adjustment time scale is short compared to the motion of the bodies).
This methodology allows a large amount of CFD data for staging aerodynamic disturbances to be produced for
detailed Monte Carlo flight simulations. Tetra Research has performed several stage separation analyses
for wind tunnel and flight conditions using CFD and has also developed 1-D analysis methods that quickly
model the dynamic separation event using CFD aerodynamic inputs.