Fan Blade Damping System for Gas Turbine Engines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fan blades in gas turbine engines experience high dynamic stress due to inlet distortion, flutter, and post bird ingestion runon, leading to reduced life from elevated vibratory stresses exceeding fatigue capability.
Innovation Solution
A hollow airfoil design with an internal damping system, incorporating partial ribs and elastomeric damping material within compartments, oriented to attenuate vibratory stress without aerodynamic interference, and manufacturing methods to form specific airfoil contours and attach damping plates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If fan blades operate in high dynamic stress environments (inlet distortion, flutter, bird ingestion), then the blade experiences elevated vibratory stresses, but this exceeds fatigue capability resulting in reduced fan blade life
Solution Approach 1:
The patent converts the harmful vibratory stresses into beneficial damping effects by incorporating vibration-damping material within the blade structure. The damping material absorbs and dissipates the vibratory energy that would otherwise cause fatigue damage, transforming the harmful stress environment into a protective mechanism that extends blade life.
Solution Approach 2:
The patent nests the vibration-damping material within the internal structure of the fan blade, specifically within cavities or compartments of the blade anatomy. This nested configuration allows the damping material to be integrated into the blade without adding external attachments, thereby protecting the blade internally while maintaining aerodynamic performance.
2Reliability
If damping material is added to reduce vibration, then fan blade life is improved, but the blade structure becomes more complex
Solution Approach 1:
The vibration-damping material is nested within existing internal cavities and compartments of the fan blade structure. By utilizing the blade's existing anatomical features rather than adding external components, the solution reduces structural complexity while still achieving vibration damping and improved blade life.
3Reliability
If internal damping structures are added to the blade, then vibration is reduced, but manufacturing complexity increases
Solution Approach 1:
The damping material is integrated into the blade manufacturing process itself, where cavities are prepared during blade formation and the damping material is inserted or applied before final assembly. This preliminary action incorporates the damping function into the base manufacturing workflow, avoiding the need for separate post-manufacturing steps and reducing overall manufacturing complexity.
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 vibration in fan blades by internal damping, enhancing their life and durability while maintaining aerodynamic performance.
Implementation Method 1
incorporating partial ribs and elastomeric damping material within compartments, oriented to attenuate vibratory stress
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A fan blade (100) having a damping system (200) is provided. The fan blade (100) comprising: a fan blade body (101) having one or more compartments (152, 162) within the fan blade body (101); a damping material (210) located within at least one of the one or more compartments (152, 162); one or more partial ribs (105) originating at the fan blade body (101) and extending into at least one of the one or more compartments (152, 162), wherein each of the one or more partial ribs (105) terminate at a distal end (105a); and one or more damping plates (220), wherein each of the one or more damping plates (220) are attached to a distal end (105a) of a partial rib (105), wherein the damping material (210) is located between the damping plate (220) and the fan blade body (101).