Launch Environment Water Flow Simulations Using Smoothed Particle Hydrodynamics

One of the crucial ground structures employed at the launch pad during the Space Shuttle program is the rainbird nozzle system, whose primary objective is to suppress acoustic energy generated by the launch vehicle during pad abort and nominal operations. It is important that the rainbird water flow does not impinge on the rocket nozzles and other sensitive ground support elements. For the new Space Launch System (SLS) vehicle, the operation is similar, regardless of the new mobile launcher and new engine configurations. The goal of the rainbird nozzle system remains sound suppression (SS), and the rocket engines still cannot get wet. However, the rearrangement of the rainbird water system for the SLS mobile launcher locates the rainbirds closer to the first-stage rocket engines, which are positioned above the exhaust hole. The close proximity of the rainbird nozzle system could potentially cause vehicle wetting during liftoff.