Prediction on the Excitation Loads and Vibratory Response of the Supersonic Flight Vehicle with Air Breathing Inlet

Abstract

This thesis presents an estimation methodology on the vibratory response of the supersonic flight vehicle caused by various dynamic loads during operation. High-speed flight vehicle (HSFV) is an imaginary supersonic flight vehicle with an air breathing engine (i.e., ramjet engine). It undergo severe dynamic loads which are generated during the launch and in-flight environments. And a typical vehicle is composed of thin plate skin structures with high-performance electronic units sensitive to such vibratory loads. Such lightweight structures are then exposed to external dynamic loads which consist of random excitation, shock, and acoustic loads created under the operating environments. Three types of dynamic loads (acoustic loads, rocket motor self-induced excitation loads and aerodynamic fluctuating pressure loads) are considered as major components in this thesis. Generally, for large structural components such as an entire launch vehicle considering high frequency range, proper structural response analysis method should be chosen because it is known that deterministic method (such as finite element analysis) is not capable of precisely and efficiently predicting the response for high frequency ranges. To overcome such limitations of the deterministic method for high frequency range, statistical energy analysis is used in this thesis. The estimation results are compared with respect to the design specification (MIL-STD-810) to examine the appropriateness. The objective of this thesis is to study an estimation methodology which helps to establish design specification for the dynamic loads acting on the vehicle which cannot be followed general design procedure because there exit a little data can be applied to establish design dynamic loads.