Integrated Design and Analysis of Intakes and Nozzles in Air-Breathing Engines

A numerical technique is described for the design and analysis of the flow in air intakes and nozzles. The design concept is considered as an integrated design in which the nozzles and intake are parts that communicate with the system as a whole. The unsteady Euler equations are numerically integrated using a time-dependent procedure and adopting a finite volume approximation. In analysis mode, simple models simulate the components linking intake and nozzles, that is, compressor, combustor, and turbine. The external flow, intake, and nozzle flows are then computed simultaneously. In design mode, the procedure used to fit plume interfaces is also used to solve an additional inverse problem and to find the nozzle (or intake) shape that matches a prescribed pressure distribution at the wall. The procedure is explained through several numerical examples of increasing complexity. (Author)