Patent ID: 6016651
Filing Date: 2000-01-25
Classification: B33Y,B64D,F02K,Y02T

Abstract:
A multi-stage mixer/ejector (20) operative to suppress the infrared signature radiated from a primary flow PF of high-temperature exhaust of an engine (12), the multi-stage mixer ejector (20) having tandemly arranged first and second stage exhaust nozzles (24, 28), and a shroud means (32) enveloping the exhaust nozzles (24, 28), said exhaust nozzles (24, 28) in combination with said shroud means (32), operative to entrain a secondary flow SF of low-temperature gaseous fluid into the primary flow;the first stage exhaust nozzle (24) including:an inlet conduit (36) adapted for receiving the primary flow PF of engine exhaust;a plurality of adjoined lobes (30) integrally formed in combination with said inlet conduit (36) and defining an outlet end of the exhaust nozzle (24), each of said adjoined lobes (30) being substantially radially oriented with respect to a longitudinal axis (24.sub.A) defined by said outlet end, said adjoined lobes (30), in combination with said shroud means (32), being adapted for admixing the secondary flow SF of low-temperature gaseous fluid with said primary flow PF of engine exhaust;said multi-stage ejector (20) being characterized by:said adjoined lobes (30) of said first stage exhaust nozzle (24) defining a first and second plurality of penetrating lobes (60, 62), said penetrating lobes (60, 62) each defining an external flow trough (30.sub.EFT), said external flow troughs (30.sub.EFT) of said first plurality (60) defining a core region (CR);said second plurality of penetrating lobes (62) projecting axially downstream of said first plurality of penetrating lobes (60) and extending into said core region (CR) so as to direct the secondary flow SF of low temperature gaseous fluid into the primary flow PF of engine exhaust.