Design And Analyses Of A Three-Dimensional Isolator With Wedges

A design method for a three-dimensional non-rectangular isolator with flow control by means of wedges is proposed in this thesis. Meanwhile, numerical simulations are performed to compare and analyze the design parameters. As a result, a set of preliminary design and analysis methods for the three-dimensional non-rectangular isolator are established.Based on the overall requirements of the scramjet, stream thrust analysis is carried out to define appropriate flow parameters at inlet and outlet boundaries. Thereafter, with a given shape of the inlet, the conceptual design of the isolator is conducted by using the empirical length formula. Finally, the isolator is further truncated with the passive wedge flow control.The numerical method used in the present thesis, in terms of discretization scheme, turbulent model, mesh size and so on, is chosen by comparisons between numerical results and well-known experimental observations. The stability and precision of the numerical method utilized are validated by a serial comparison between numerical simulations and experimental results.Effects of the wedge flow control on the designed isolator performance are studied with the numerical method used. Complex flow phenomena and related mechanism in the isolator with wedge flow control are simulated and analyzed. Effects of shape parameters, such as length, height and so on, on the isolator performance are investigated. With a fixed wedge shape, the arrangement of the wedge in the isolator is studied, and thus valuable suggestions for engineering applications of a three-dimensional non-rectangle isolator with the wedge flow control are provided.