Rotor Blade Tip Clearance via Center of Gravity Offset
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inconsistent radial displacements of the leading edge and trailing edge of rotor blade tips in compressor blades lead to airflow leakage or scraping issues, affecting aerodynamic performance and safety in aeroengines.
Innovation Solution
A method that adjusts the center of gravity of the rotor disk to equalize the radial deformation of the leading and trailing edges of the rotor blades by measuring and offsetting the center of gravity based on deformation amounts, ensuring consistent tip clearance without additional mechanisms.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the rotor blade airfoil design focuses on aerodynamic performance and stress, then the aerodynamic performance is improved, but the radial deformation difference between leading edge and trailing edge is not controlled, causing inconsistent tip clearance
Solution Approach 1:
The patent applies preliminary action by pre-setting the center of gravity offset of the rotor blade before operation. This offset is calculated based on the expected radial deformation characteristics, allowing the blade to automatically compensate for deformation differences between leading and trailing edges during rotation, thereby maintaining consistent tip clearance without real-time control mechanisms
Solution Approach 2:
The patent changes the physical parameter of the rotor blade's center of gravity position by introducing a deliberate offset from the elastic axis. This parameter change alters the blade's deformation behavior under centrifugal and aerodynamic loads, equalizing the radial displacement at leading and trailing edges to achieve uniform tip clearance
2Reliability
If the rotor blade tip clearance is made small to improve aerodynamic performance, then efficiency is improved, but the risk of scraping the casing increases
Solution Approach 1:
The patent applies self-service by designing the rotor blade with an inherent center of gravity offset that automatically adjusts the blade's radial position during operation. This self-adjusting mechanism ensures the blade maintains optimal tip clearance without external control systems, preventing both excessive clearance (reducing efficiency) and insufficient clearance (causing scraping)
3Manufacturing precision
If additional control devices are added to adjust tip clearance, then the tip clearance control precision is improved, but the device complexity and cost increase
Solution Approach 1:
The patent eliminates the need for additional control devices by incorporating the tip clearance control function directly into the rotor blade design through center of gravity offset. The blade automatically equalizes its radial deformation and maintains consistent tip clearance through its inherent structural configuration, achieving precise control without external mechanisms
Solution Approach 2:
The patent merges the tip clearance control function with the rotor blade structure itself by integrating the center of gravity offset design into the blade's elastic axis configuration. This consolidation eliminates separate control systems and achieves clearance control as an inherent property of the blade design
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
This method improves aerodynamic performance by maintaining consistent rotor blade tip clearance, preventing airflow leakage and scraping, and ensuring safe operation of aeroengines without redundant parts or mechanisms.
Implementation Method 1
rotating the rotor disk
Data Source
AI summary
A rotor blade tip clearance control method and a rotor blade manufactured using same. The control method includes: coinciding, along an axial direction of an aircraft engine, a center of gravity of a rotor blade with a center of gravity of a rotor wheel disk supporting the rotor blade; rotating the rotor wheel disk to measure a leading edge deformation amount of the rotor blade; measuring a trailing edge deformation amount of the rotor blade; comparing the deformation amounts; and adjusting the center of gravity of the rotor wheel disk until the leading edge deformation amount tends to be approximately equal to the trailing edge deformation amount. The method can effectively improve or even solve the problem of inconsistent radial displacements of a leading edge and a trailing edge during the operation.