Summary: | 碩士 === 國防大學中正理工學院 === 兵器系統工程研究所 === 92 === Inspired by the fact that turbulent combustion is a popular phenomenon existing in the burner of most ramjet and liquid rocket propulsion systems and playing a role in determining the system performance, the present thesis proposes a fundamental study of the vortex interaction phenomenon, which is believed to be a common basis of turbulent combustion flows, so that the result may further be applied to the burner design and performance assessment of these systems. In contents, the study consists of three major parts: (1) a theoretical investigation of the effects due by burner efficiency changes and total pressure loss on the performance of a typical ramjet engine, using a simulation method based on aerothermodynamics and fundamental conservation laws, (2) a general analysis of the interaction of two vortices, based on flow kinematics and coordinate transformation relations, with focus on the transient structure of the resultant flow, (3) an extension of the two-vortex-interaction study to typical multiple-vortex-interaction cases, such as the flows near wall and injectors. Major results thus obtained through this thesis study include: (i) the development of a practical software package, named CSJP-9, which may be used to simulate the design point performance of typical ramjets with given conditions, and as an investigation tool for the key factors in determining the burner performance, (ii) the identification of a periodical displacement for the center of an asymmetric two-vortex-interaction system (CATVIS), which may serve as a possible entrance for further studies of combustion instabilities and noises problem, (iii) the setup of a practical architecture for successive investigations of the vortex-flame interaction associated with turbulent combustion.
|