An analysis of the problems associated with matching secondary-air requirements of ejector exhaust nozzles and auxiliary inlets was made for free-stream Mach numbers up to 2.0. A method for matching the components is presented. The analysis indicated that inlets located in the free stream supply higher pressure recovery than ejectors generally require for optimum net internal thrust at Mach numbers above about 1.4. Consequently, net-thrust gains may be achieved by immersing the auxiliary inlet in a boundary layer where the inlet-momentum penalty is less. At a free-stream Mach number of 2.0 a variable-inlet - variable ejector configuration would develop 9.5 percent more thrust than a convergent nozzle. A fixed-inlet - fixed-ejector combination designed for a Mach number of about 1.7 would develop net thrust within 5 percent of that possible with a variable-inlet - variable-ejector system over the entire Mach number range considered (0 to 2.0). (Author)
Matching of Auxiliary Inlets to Secondary-Air Requirements of Aircraft Ejector Exhaust Nozzles
1955
43 pages
Report
No indication
English