THRUST REVERSER FOR FLUID FLOW ENGINE

• US 3,717,304 A
• Filed: 05/03/1971
• Issued: 02/20/1973
• Est. Priority Date: 05/06/1970
• Status: Expired due to Term

• Current Assignee: Julian Macdonald Davison Sutton
• Original Assignee: Julian Macdonald Davison Sutton
• Inventors: Sutton, Julian MacDonald Davison
• Primary Examiner(s): King, Lloyd L.
• Application Number:
  US05/139,693
• Time in Patent Office: 659 Days
• Field of Search: 239/265.19,265.25,265.27,265.29,265.31
• US Class Current: 239/265.19
• CPC Class Codes: F02K 1/563 in specified direction, e.g. to obviate its reinjection
• CPC Class Codes: F02K 1/70 using thrust reverser flaps or doors mounted on the fan housing
• CPC Class Codes: F02K 1/72 the aft end of the fan housing being movable to uncover openings in the fan housing for the reversed flow

Abstract

Gas turbine ducted fan engines having short intakes suffer from re-ingestion problems when reverse fan thrust is selected. The present invention profiles the column of reversed fan air so that it presents a weaker front to the ambient airstream which is able to peel off the reversed fan air from the cowl before reingestion occurs.

Claims

1. A gas turbine ducted fan engine fan cowl comprising upstream and downstream annular portions axially separable from each other to define an annular space therebetween, and at least two sets of air flow deflector means arranged to lie in alternate side-by-side relationship with each other circumferentially of said cowl, so as to be within said annular space when formed, one set of said air flow deflector means being positioned so that, in operation, fan air flowing therethrough is deflected at a first acute angle to a longitudinal axis of said fan cowl and the other set of said air flow deflector means being positioned so that, in operation, fan air flowing therethrough is deflected at a second acute angle to the longitudinal axis of said fan cowl.

2. A gas turbine ducted fan engine fan cowl fan cowl as claimed in claim 1 wherein at least one of the sets of air flow deflector means comprises a plurality of discrete nozzles.

3. A gas turbine ducted fan engine fan cowl as claimed in claim 1 wherein both sets of fan air flow deflector means comprises scallops formed on the upstream edge of said downstream annular cowl portion, said scallops providing a staggered edge whereby to effect differing angles of fan air flow.

4. A gas turbine ducted fan engine fan cowl as claimed in claim 1 wherein said one set of air flow deflector means comprises a plurality of cascades having vanes set at said first acute angle to the longitudinal axis of said fan cowl and wherein the other air flow deflector means comprises a plurality of cascades having vanes set at the second acute angle relative to the longitudinal axis of said fan cowl.

5. A gas turbine ducted fan engine fan cowl as claimed in claim 1 including means to provide an annular space in said upstream portion of said fan cowl to define a further upstream intake for said fan cowl.

6. A gas turbine ducted fan engine fan cowl as claimed in claim 1 including means to selectively cover said annular space.