Modular Chevron Exhaust Nozzle for Gas Turbine Engines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The manufacturing of two-ply chevron exhaust nozzles for gas turbine engines faces challenges in achieving smooth, flush surfaces for maximum aerodynamic efficiency and minimizing serpentine trailing edge losses, while also dealing with the complexity of unitary configurations that can be prone to damage or manufacturing errors, affecting overall performance.
Innovation Solution
A modular chevron design featuring dual skins fixedly joined at a base flange and rim, with each chevron being a unitary assembly that can be independently manufactured and assembled, providing structural rigidity and aerodynamic performance while allowing for varying sizes and configurations to optimize noise attenuation and efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a two-ply construction is used for the chevrons to achieve smooth, flush surfaces for maximum aerodynamic efficiency, then aerodynamic performance is improved, but manufacturing complexity and difficulty increase significantly
Solution Approach 1:
The chevron nozzle is divided into multiple individual chevron elements rather than being constructed as a single unitary two-ply structure. Each chevron element can be manufactured separately with simpler processes, then assembled to form the complete nozzle. This segmentation reduces the manufacturing complexity of achieving smooth, flush surfaces while maintaining the aerodynamic benefits of two-ply construction in critical areas.
2Strength
If a unitary configuration of annular chevrons is used to enhance structural rigidity and strength, then structural integrity is improved, but manufacturing difficulty increases and damage to individual chevrons affects the entire nozzle performance
Solution Approach 1:
The nozzle is segmented into multiple independent chevron elements that are assembled together rather than manufactured as a single unitary structure. This allows each element to be manufactured separately with easier processes, reduces the impact of damage to individual elements, and maintains overall structural rigidity through proper assembly and connection design.
Solution Approach 2:
The design transitions from a unitary continuous structure to a modular segmented structure, changing the structural parameter from monolithic to composite assembly. This parameter change enables easier manufacturing of individual elements while maintaining structural integrity through the collective arrangement and connection methods of the segmented components.
3Strength
If full annular rings are used for the nozzles to accommodate large pressure loads, then structural strength is improved, but noise attenuation capability is reduced
Solution Approach 1:
The full annular ring is segmented into individual chevron elements with gaps between them. This segmentation creates the serpentine trailing edge configuration that enhances noise attenuation through flow mixing, while each element maintains sufficient structural strength to accommodate pressure loads. The collective arrangement of segmented elements provides both noise reduction and structural capability.
Data Source
AI summary
An exhaust nozzle for a gas turbine engine includes a modular chevron. The chevron includes dual skins fixedly joined together at a base flange, and at a rim extending along the trailing edge of the chevron between the base and apex thereof.