Stage Separation

Stage Separation Using Loci/CHEM

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 flight event can be effectively modeled using CFD. In some cases, stage separation can be treated using a quasi-steady assumption to decouple the relative motion of the two bodies from the fluid dynamics (this is valid if the fluid dynamics time scale is short compared to the body motion time scale). While this approach can produce a large amount of CFD data for use in Monte Carlo flight simulations, it fails to capture the dynamics of the separation event.

The Loci/CHEM team has developed modules to simulate the full six degrees of freedom (6 DOF) relative motion of the separating bodies. The methodology couples the aerodynamics and propulsion to the integrated body motion along the flight trajectory. Overset unstructured grids with advanced hole cutting and interpolation procedures provide a robust tool that can be used for the analysis of stage and store separation systems, launch simulations, or other types of multiple bodies in relative motion.

Read More About Rocket Staging

Learn more about rocket propulsion and read how a multi-stage rocket works.