Integrated Bleed Valve Resonator for Compressor Duct Resonance
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Solution Overview
Problem
Gas turbine engines face instability issues due to resonance in bleed ducts, which can damage compressor blades, particularly during start, transient, and reverse thrust operations, as existing technologies do not effectively manage vibrational waves caused by airflow.
Innovation Solution
A low pressure compressor case with a second bleed duct and a second bleed valve assembly, featuring a resonator chamber system with varying dimensions to alter resonation properties and change the frequency of vibrational waves, including a 2.5 bleed valve assembly with a manifold, chamber body, and resonator cover, to prevent damage to compressor blades.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a resonator chamber is added to the bleed valve assembly to suppress vibrational waves, then blade damage is reduced and stability is improved, but device complexity increases
Solution Approach 1:
The resonator chamber is integrated into the bleed valve assembly by merging it with the valve body structure. The chamber forms part of the overall valve housing, combining the bleeding function and resonance suppression function into a single integrated component rather than separate additions.
Solution Approach 2:
The bleed valve assembly is designed to perform multiple functions: it controls bleed air flow from the compressor section and simultaneously suppresses vibrational waves through the integrated resonator chamber. This multi-functionality reduces the need for separate components.
2Reliability
If the resonator chamber volume is increased to improve vibration suppression, then blade damage reduction is enhanced, but the space required in the compressor case increases
Solution Approach 1:
The resonator chamber is positioned in a specific location within the bleed valve assembly where it can effectively intercept and suppress vibrational waves. The chamber's dimensions and positioning are optimized for local vibration control rather than requiring large overall volume.
Solution Approach 2:
The resonator chamber dimensions are carefully selected to change the resonant frequency of the system, matching it to the problematic vibrational frequencies. By adjusting the chamber volume and shape parameters, effective vibration suppression is achieved with minimal space requirement.
3Reliability
If the resonator chamber height is varied to optimize resonance frequency, then vibration control is improved, but manufacturing precision requirements increase
Solution Approach 1:
The resonator chamber is designed with asymmetric dimensions where the height varies differently from other dimensions. This asymmetric design allows optimization of the resonant frequency through the height parameter while the other dimensions can be manufactured with standard tolerances, reducing overall manufacturing precision requirements.
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 solution effectively reduces blade damage by altering the frequency of vibrational waves, providing stability during critical operations and extending the lifespan of compressor blades.
Implementation Method 1
A resonator chamber is in fluid communication with the bleed duct... alter resonation properties and change the frequency of vibrational waves
Data Source
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AI summary
Bleed valve assemblies (300) in a gas turbine engine (100) are disclosed herein. A bleed valve assembly (300) in a low pressure compressor (150) may include a bleed valve (230; 310) and a resonator chamber (500; 610, 620). A manifold (400) may allow passage of air from a bleed duct (230; 310) into the resonator chamber (500; 610, 620). The resonator chamber (500; 610, 620) may alter resonation properties of the bleed duct (230; 310) in order to prevent damage to components in the low pressure compressor (150).