Abstract
The concept of a variable cycle turbofan engine with an axially supersonic fan stage as powerplant for a Mach 2.7 supersonic transport was evaluated. Quantitative cycle analysis was used to assess the effects of the fan inlet and blading efficiencies on engine performance. Thrust levels predicted by cycle analysis are shown to match the thrust requirements of a representative aircraft. Fan inlet geometry is discussed and it is shown that a fixed geometry conical spike will provide sufficient airflow throughout the operating regime. The supersonic fan considered consists of a single stage comprising a rotor and stator. The concept is similar in principle to a supersonic compressor, but differs by having a stator which removes swirl from the flow without producing a net rise in static pressure. Operating conditions peculiar to the axially supersonic fan are discussed. Geometry of rotor and stator cascades are presented which utilize a supersonic vortex flow distribution. Results of a 2-D CFD flow analysis of these cascades are presented. A simple estimate of passage losses was made using empirical methods.
Publication Date
8-22-1985
Journal Title
NASA Technical Reports Server
Publisher
United States
Document Type
Report
Recommended Citation
Tavares, T.S., “A Supersonic Fan Equipped Variable Cycle Engine for a Mach 2.7 Supersonic Transport,” NASA-CR-177141, 1986.
Comments
This report can be found on the NASA Technical Reports Server: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19860019474.pdf