Turbine Engine Oxidizer Enhanced Duct Burner Mode

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing turbofan engines are limited in exceeding certain Mach numbers due to drag, cooling, and operational constraints, preventing them from achieving higher speeds even with features designed to mitigate these issues.

Innovation Solution

A turbine engine structure that transitions between turbofan and duct burner modes, with the option of oxidizer enhancement, utilizing a fan connected to a turbine engine core via a shaft, a nacelle, and augmenter fuel spray bars that operate as a duct burner, and a jet fuel motor that drives the fan and core, along with a controller to manage these modes and oxidizer injection for increased thrust.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If conventional turbofan engine operation is used, then the engine operates efficiently at low to medium speeds, but the engine cannot exceed certain Mach numbers due to drag and cooling limitations

Engineering Contradiction:

ImproveMach numberVSAvoiddrag and cooling limitations

Core Design Contradiction:

SpeedVSObject-affected harmful factors

Solution Approach 1:

The engine dynamically transitions between turbofan mode and duct burner mode based on operating conditions. The duct burner system is activated at higher Mach numbers to provide additional thrust, while the turbofan core continues to operate. This dynamic mode switching allows the engine to adapt to different speed regimes and overcome the speed limitations of conventional turbofan operation.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention changes the thermodynamic parameters of the engine by introducing a duct burner that injects fuel and oxidizer into the bypass flow. This creates a second combustion chamber that operates independently from the core engine, allowing the engine to operate with different thrust levels and thermal characteristics suitable for high-speed flight.

Inventive Principle:

Principle #35Parameter changes

2Speed

If a duct burner is added to provide additional thrust at high speeds, then the engine can operate at higher Mach numbers, but the device complexity increases

Engineering Contradiction:

ImproveMach numberVSAvoidengine structure

Core Design Contradiction:

SpeedVSDevice complexity

Solution Approach 1:

The duct burner system is designed to serve multiple functions: it provides additional thrust at high speeds, can be used for rapid acceleration, and can operate in conjunction with the turbofan core or independently. The same duct burner infrastructure serves different operational requirements, reducing the need for separate systems for each function.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The duct burner system is nested within the existing turbofan engine architecture. The duct burner injects fuel and oxidizer into the bypass flow path that already exists in the turbofan engine, rather than requiring a completely separate combustion system. This nested approach allows the high-speed capability to be integrated into the existing engine structure.

Inventive Principle:

Principle #7Nested doll (Nesting)

3Power

If oxidizer injection is used to enhance duct burner performance, then thrust is increased for high-speed operation, but the quantity of substance required increases

Engineering Contradiction:

ImprovethrustVSAvoidoxidizer

Core Design Contradiction:

PowerVSQuantity of substance

Solution Approach 1:

The oxidizer is injected locally at specific positions in the duct burner system where it is most needed for combustion. The oxidizer injection is concentrated in regions of high velocity and temperature where it can most effectively enhance the combustion process and generate additional thrust, rather than being distributed uniformly throughout the engine.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The oxidizer injection system is designed to provide just enough oxidizer to enhance the duct burner performance at high speeds, rather than providing excessive oxidizer that would be unnecessary at lower speeds. The oxidizer flow rate is modulated based on operating conditions to match the actual thrust requirements.

Inventive Principle:

Principle #16Partial or excessive action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enables the engine to operate efficiently at higher Mach numbers by providing additional thrust through duct burning and oxidizer enhancement, overcoming the speed limitations of conventional turbofan and duct burner engines.

Implementation Method 1

a plurality of augmenter fuel spray bars disposed in the bypass flowpath

Methodology Applied

Scientific EffectCombustion: Combustion

Implementation Method 2

an oxidizer injector configured to at least partially supplement air in the bypass flowpath with an oxidizer

Methodology Applied

Scientific EffectOxidizer injection: Injector

Implementation Method 3

a cooling system configured to cool at least one of non-core engine static structures and the fan using one of a jet fuel and an oxidizer

Methodology Applied

Scientific EffectEvaporative cooling: Evaporative Cooler

Data Source

PatentUS11041463B1Turbine engine structure with oxidizer enhanced mode

Publication Date: 2021.06.22 RTX CORP

AI summary

A turbine engine structure includes a turbine engine core having a core cocooning feature, and a fan fore of the turbine engine core, relative to fluid flow through the turbine engine structure. The fan is drivably connected to the turbine engine core via a shaft. A nacelle circumferentially surrounds the turbine engine core, and a bypass flowpath is defined between the turbine engine core and the nacelle. A plurality of augmenter fuel spray bars are disposed in the bypass flowpath.