On the design of a high-subsonic jet transport aircraft with particular reference to thrust-vectoring

摘要

The conceptual design of a jet civil transport aircraft with and without thrust- vectoring is considered. The project studies thrust-vectoring effects using externally adjustable exhaust nozzles on the design of a high-subsonic civil jet transport aircraft with twin wing-mounted turbofan engines. The status, importance and classifications of thrust- vectoring technology are presented and some examples of thrust vectored civil and military aircraft are given. A literature survey, a discussion of the theoretical, computational and experimental work along with an outline for future work are given. In order to achieve these goals, a convergent iterative computer program (ICP) was written in FORTRAN-77 for the UNIX computer operating system. It is for the preliminary design of a high-subsonic jet transport aircraft and airworthiness regulations were adhered to throughout the design. By using a series of subroutines, the program is structured so that the effects of any change in the design parameters can be readily evaluated and future improvements and expansions can easily be made. The ICP uses a step-by-step method to integrate along the flight path and the output is presented after several iterations when there are no further changes. An experimental study has been conducted, using the Goldstein Laboratory's open-return Project Wind-Tunnel with a closed working-section. This experimental work produced the aerodynamic force coefficients and the induced-drag factors of different combinations of six wings and two jets with circular and rectangular' nozzle exits.The experimental wing-jet-flap configurations with jet deflections were modelled by the Vortex Lattice Method (VLM) using a NASA code, slightly modified for this project. Experimental and VLM results are presented for the thrust-vectoring effects on the force coefficients for the wing-jet-flap combinations at different jet velocities, wing angles of attack, nozzle pitch, yaw angles and nozzle exit shapes. The pressure and velocity distributions, predicted by the VLM code, for the six wings in the vicinity of the jet engines were also displayed. Different circular and rectangular nozzles at various angles have been used to provide these jet deflections. Estimates have been obtained for the resulting modification to the induced drag and extra-circulation. Only the preliminary design stage of a civil jet transport aircraft is considered and no detailed study of the dynamic stability, the structure or the economics of the aircraft is given in this thesis. (Abstract shortened by ProQuest.).