Compressor Blade Undercut Reduces Vibratory Stress
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gas turbine engine rotating components, particularly compressor blades, face challenges in effectively reducing vibratory stresses, which can lead to structural failures and inefficiencies.
Innovation Solution
The implementation of a unique turbomachinery blade design featuring an undercut beneath the trailing or leading edge of the airfoil section, which alters the stiffness of the blade to redirect load paths away from critical stress areas, thereby mitigating vibratory stresses through the use of tailored undercut shapes and positions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional compressor blade design is used, then the blade structure is simple and easy to manufacture, but the blade cannot effectively reduce vibratory stresses leading to structural failures
Solution Approach 1:
The patent applies local quality by introducing an undercut feature specifically at the trailing edge of the airfoil, rather than modifying the entire blade structure. This localized modification changes the stiffness distribution only where needed to redirect load paths and reduce vibratory stresses, maintaining simplicity in other areas while improving reliability at critical stress concentration points
Solution Approach 2:
The undercut feature segments the continuous blade structure into distinct regions with different stiffness characteristics. By creating this discontinuity at the trailing edge, the blade is divided into zones that can independently manage stress distributions, allowing the structure to better withstand vibratory loads without requiring complete redesign of the entire blade
2Strength
If blade stiffness is increased to withstand vibrations, then structural strength improves, but vibratory stresses are not effectively reduced and may even be amplified
Solution Approach 1:
The patent applies parameter changes by modifying the stiffness distribution along the blade length through the undercut feature. Instead of uniformly increasing blade stiffness, the undercut creates a localized change in structural parameters that redirects load paths away from the trailing edge, reducing vibratory stresses while maintaining overall blade strength through optimized stiffness distribution rather than brute-force strengthening
Data Source
AI summary
A turbomachinery blade for a gas turbine engine is provided and includes an airfoil extending between a leading edge and a trailing edge. In one embodiment the turbomachinery blade is a compressor blade. The blade can include a platform attached to the airfoil on one side, the other side being attached to a stalk having a lower attachment portion useful for being received in a compressor disk. The blade includes an undercut beneath a portion of the airfoil, preferably beneath the leading edge and/or trailing edge of the airfoil. In one form the undercut is located in a corner of the platform and extends partially along two sides of the platform.