NUMERICAL APPROACH FOR COMPUTING NOISE-INDUCED VIBRATION FROM LAUNCH ENVIRONMENTS

The development, implementation, and validation of a new numerical algorithm for predicting noise-induced vibration from acoustic loads experienced during launch vehicle liftoff are presented. The development is based on combination of boundary element and Ž nite element technology. Two new important advancements are included and validated in this work: the existence of unequalmesh density between the structural and the acoustic model at their interface and the numerical simulation of a reverberant Ž eld as an acoustic environment. Results produced for an expanding nozzle of a rocket are compared successfully with test data. This development can be utilized during the initial and preliminary design phases of launch vehicles, when guidance can have signiŽ cant impact.

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