Gas Turbine Rotor Disk Stress Distribution via Protrusions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Gas turbine engine rotor sections experience substantial stress during operation, leading to reduced component lifespan, and existing balancing methods either fail to adequately address stress concentration or introduce new issues.
Innovation Solution
The design incorporates mismatch and balancing protrusions with specific fillet radii and web surface configurations on rotor disks to distribute stress more evenly, including mismatch and balancing plateaus with fillets transitioning to web surfaces, which are machined to reduce stress concentration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If rotor disk balancing is performed using conventional methods, then some stress distribution improvement is achieved, but stress concentration at fillet intersections remains significant
Solution Approach 1:
The patent applies local quality by creating mismatch protrusions with specific geometric characteristics (plateau region with larger fillet radii) at critical stress concentration locations. The fillet radius varies locally - larger at the plateau intersection to reduce stress concentration, and smaller at web surfaces to maintain structural integrity. This localized geometric modification directly addresses stress distribution without compromising overall disk strength.
Solution Approach 2:
The invention changes the geometric parameters of the rotor disk structure by introducing mismatch protrusions with controlled fillet radii (0.1-0.3 times the blade root depth). The plateau region is positioned at specific radial and axial locations to optimize stress distribution. This parameter modification transforms the stress concentration pattern while maintaining the disk's load-bearing capacity.
2Reliability
If larger fillet radii are used at mismatch intersections, then stress concentration is reduced, but disk thickness and weight increase
Solution Approach 1:
The mismatch protrusions are localized to specific regions where stress concentration occurs most severely. The plateau region with enlarged fillet radii is positioned only at the critical intersection zone, not throughout the entire disk thickness. This localized approach reduces stress concentration while minimizing the added weight compared to a uniform thickening of the entire disk.
Solution Approach 2:
The invention applies partial action by introducing mismatch protrusions only at critical stress concentration locations rather than uniformly throughout the disk. The protrusions extend only partially through the disk thickness, with the plateau region positioned to provide maximum stress relief where needed while maintaining minimal material addition. This selective application optimizes the balance between stress reduction and weight increase.
Data Source
Figure 1
Figure 2~4
Figure 5~6
AI summary
A rotor disk includes a web that extends in a radial direction from a rim on a radially outer end to a bore on a radially inner end. The web includes a mismatch protrusion on a first axially facing surface of the web. A balancing protrusion is on a second axially facing surface of the web.