Reverse core gear turbofan

Patent metadata

Field	Value
Publication number	US-10107193-B2
Application number	US-201514824157-A
Country	US
Kind code	B2
Filing date	Aug 12, 2015
Priority date	Mar 27, 2012
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

A gas turbine engine comprises a fan at an axially outer location, the fan rotating about an axis of rotation, delivering air into an outer bypass duct, a radially middle duct, and a radially inner core duct. Air from the inner core duct is directed into a compressor, and then flows axially in a direction back toward the fan through a combustor section, and across a core turbine section, and is then directed into the middle duct. A gear reduction drives the fan from a fan drive turbine section. A method of operating a gas turbine engine is also disclosed.

First claim

What is claimed is:

1. A method of operating a gas turbine engine comprising the steps of:
(a) operating a main turbine section having a fan drive turbine driving a fan rotor of a fan section and a cold turbine section having blades with a radially outermost extent also driving said fan rotor, said cold turbine section located upstream from a combustor section such that a flow of fan air passes from the fan section to the cold turbine section and then on to the combustor section, in that order, and a pair of flow diverters operable to divert said flow of fan air radially inwardly of the radially outermost extent of the blades, or allow said flow of fan air to pass radially outwardly of the radially outermost extent of the blades; and
(b) positioning said pair of flow diverters to increase or decrease the amount of said flow of fan air passing across said blades to increase or decrease a power output by said cold turbine section to said fan rotor.

2. The method as set forth in claim 1 , wherein said pair of flow diverters moving between a first position which passes all of the flow of fan air radially inwardly of the radially outermost extent of the blades, and to a second position which diverts all of the flow of fan air radially outwardly of the radially outermost extent, said pair of flow diverters both being pivoted radially inwards in said first position and said pair of flow diverters both being pivoted radially outwardly in said second position.

3. The method as set forth in claim 2 , wherein said pair of flow diverters is moved to the second position to allow bypass of the flow of fan air in low power conditions, such as when the gas turbine associated with the turbine section is in a aircraft at cruise conditions, and the pair of flow diverters being moved to the first position to direct the flow of fan air radially inwardly of the radially outermost extent at high power conditions, such as take-off for the aircraft.

Assignees

• United Technologies Corp

Inventors

• Kupratis Daniel Bernard
• Moon Francis R

Classifications

• F05D2220/32

  in gas turbines · CPC title

• F02C3/145

  the combustion chamber being in the reverse flow-type · CPC title

• F02C3/13

  having variable working fluid interconnections between turbines or compressors or stages of different rotors {(controlling flow ratio between different flows of multi-flow jet-propulsion plant, e.g. ducted fan F02K3/075)} · CPC title

• F01D17/141

  by means of shiftable members or valves obturating part of the flow path · CPC title

• F05D2260/4031

  as in toothed gearing · CPC title