Turboprop Nozzle Junction Segmentation for Cooling

Solution Overview

Problem

Aircraft turboprop engines with unducted fans face challenges in cooling due to heat diffusion between the inner and outer walls of nozzles, leading to limited cooling capacities and increased mass with complex duct setups for air circulation.

Innovation Solution

A nozzle design with a junction area between the inner and outer walls featuring discrete openings and connecting pads or plates, eliminating the need for a circumferential annular junction area and cold air circulation pipes, thereby enhancing ventilation and reducing mass.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If a circumferential annular junction area with cold air circulation ducts is used to cool the engine, then cooling capacity is improved, but device complexity and mass increase significantly

Engineering Contradiction:

Improvecooling capacityVSAvoidduct setup complexity

Core Design Contradiction:

TemperatureVSDevice complexity

Solution Approach 1:

The continuous annular junction area is segmented into discrete localized openings distributed around the nozzle. Instead of a circumferential annular junction area forming a continuous cooling duct, the patent employs multiple separate openings (at least three) arranged circumferentially, which simplifies the structure while maintaining cooling effectiveness through distributed air flow paths.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The complex cold air circulation duct system is extracted and replaced by simple localized openings in the junction area. The patent removes the need for elaborate ductwork by directly opening cooling passages through the junction area between inner and outer walls, allowing cold air to circulate without requiring complex duct connections.

Inventive Principle:

Principle #2Taking out (Extraction)

2Temperature

If a circumferential annular junction area with cold air circulation ducts is used to cool the engine, then cooling capacity is improved, but mass increases considerably

Engineering Contradiction:

Improvecooling capacityVSAvoidnozzle mass

Core Design Contradiction:

TemperatureVSWeight of moving object

Solution Approach 1:

The continuous annular junction area is segmented into discrete localized openings distributed around the nozzle. Instead of a circumferential annular junction area forming a continuous cooling duct, the patent employs multiple separate openings (at least three) arranged circumferentially, which simplifies the structure while maintaining cooling effectiveness through distributed air flow paths.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The complex cold air circulation duct system is extracted and replaced by simple localized openings in the junction area. The patent removes the need for elaborate ductwork by directly opening cooling passages through the junction area between inner and outer walls, allowing cold air to circulate without requiring complex duct connections.

Inventive Principle:

Principle #2Taking out (Extraction)

3Strength

If a continuous annular junction area is used between inner and outer walls, then structural integrity is maintained, but heat diffusion limits cooling capacity

Engineering Contradiction:

Improvestructural integrityVSAvoidcooling capacity

Core Design Contradiction:

StrengthVSTemperature

Solution Approach 1:

The continuous annular junction area is segmented into discrete localized openings distributed around the nozzle. Instead of a circumferential annular junction area forming a continuous cooling duct, the patent employs multiple separate openings (at least three) arranged circumferentially, which simplifies the structure while maintaining cooling effectiveness through distributed air flow paths.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The junction area between inner and outer walls has different properties in different locations. The patent creates localized openings in specific regions of the junction area to enable cooling at those specific points, while the rest of the junction area maintains its structural continuity and integrity. This local modification allows cooling without compromising overall structural strength.

Inventive Principle:

Principle #3Local quality

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

The design significantly reduces the nozzle's mass, leading to lower fuel consumption and improved engine ventilation without the complexity and mass of traditional duct systems.

Implementation Method 1

By providing one or several openings in the junction area of the inner and outer walls of the nozzle, ventilation between said inner and outer walls is created, thus allowing providing a good ventilation of the engine.

Methodology Applied

Scientific EffectConvection: Convection

Data Source

PatentUS10113506B2Nozzle for an aircraft turboprop engine with an unducted fan

Publication Date: 2018.10.30 AIRCELLE SA

AI summary

The present disclosure provides a nozzle for an aircraft turboprop engine with an unducted fan, including: an inner wall, an outer wall radially spaced apart from the inner wall and concentric with the inner wall, a junction area of the inner and outer walls including an opening contained in a plane transverse to a longitudinal axis of the nozzle. In particular, the junction area of the inner and outer walls includes two connecting plates and a member to secure the two connecting plates together, or in another form, the junction area includes a pad secured to the inner wall, and a pad secured to the outer wall, facing the pad of the inner wall of the nozzle.