Ignition/duct overpressure induced by Space Shuttle solid rocket motor ignition

An analytical methodology, with a propagating solid rocket motor (SRM) exhaust front as a perturbation pressure wave generator, is developed to enhance understanding of the ignition/duct overpressure (IOP/DOP) induced during the Space Shuttle liftoff. Waveform, amplitude, and low-frequency responses of IOP/DOP are simulated. For a full-scale configuration, IOP and DOP responses are clearly isolated and distinguishable. However, in the subscale tests, an interaction region of IOP and DOP exists, which obscures interpretation of the test data. The methodology offers a first-order assessment of these phenomena with respect to the launch complex geometry and the SRM ignition transient, and provides guidance for the test data interpretation.