Effect of idealized asymmetric inhibitor stubs on circumferential flow in the Space Shuttle SRM

Computational fluid dynamic analyses have been performed to calculate circumferential pressure and velocity gradients in the vicinity of an asymmetric inhibitor stub in the port of the Space Shuttle solid rocket motor. The three-dimensional Navier-Stokes equations were solved by an iterative finite volume algorithm, SIMPLE, incorporated in a general purpose computer code, FLUENT. Turbulence was represented by way of effective viscosity, which was calculated from local turbulence energy and its dissipation rate (K- epsilon model). The numerical predictions were compared with the measurements from a 7.5% scale, cold-flow model of the redesigned solid rocket motor. The calculated circumferential pressure distribution upstream of the inhibitor stub compares well with the measured data.