Articulating Axial-Flow Compressor Rotor Blade for Variable Incidence
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional gas turbine engines face inefficiencies due to fixed rotor blade designs, which struggle to maintain optimal aerodynamic performance across varying operating conditions, leading to increased fuel consumption and noise, and require active cooling and thermal barrier coatings.
Innovation Solution
An adaptable articulating blade assembly with a suitable actuation mechanism, such as hydro-mechanical, pneumatic-mechanical, or smart material-based systems, allows for the rotation of rotor blades to adjust their pitch angle synchronously with stator vanes, optimizing incidence angles and improving aerodynamic performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional fixed rotor blade design is used, then manufacturing simplicity is maintained, but aerodynamic performance deteriorates under varying operating conditions
Solution Approach 1:
The rotor blade is designed with articulating capability allowing it to rotate about a pivot point near the leading edge, changing its pitch angle dynamically. This dynamic adjustment enables the blade to adapt to varying flow incidence angles throughout the operating range, resolving the contradiction between fixed structure simplicity and variable performance adaptability.
Solution Approach 2:
The blade structure is segmented into movable and stationary portions, with the ability to articulate at the root region. This segmentation allows independent movement of the blade airfoil relative to the hub, enabling aerodynamic optimization without requiring complete redesign of the entire engine structure.
2Adaptability or versatility
If variable turbine nozzle geometry is used, then incidence angle optimization is improved, but weight and complexity increase
Solution Approach 1:
The rotor blade itself performs the incidence angle adjustment function through articulation, eliminating the need for separate variable nozzle mechanisms. The blade serves dual purposes: maintaining its primary aerodynamic function while also adjusting its own incidence angle to optimize performance, thereby reducing additional weight and complexity.
Solution Approach 2:
The articulating rotor blade mechanism serves multiple functions: it optimizes incidence angle for aerodynamic performance, maintains structural integrity, and enables operation across extended speed ranges. This multi-functionality reduces the need for separate specialized components that would increase weight.
3Productivity
If power turbine speed is reduced for improved cruise performance, then propeller efficiency increases, but turbine blade aerodynamic performance deteriorates due to wide incidence angle variations
Solution Approach 1:
The articulating rotor blade dynamically adjusts its pitch angle in response to changing flow conditions that occur during speed transitions from hover to cruise. This dynamic adaptation allows the turbine to maintain high aerodynamic efficiency across the full operating range, enabling the propeller to operate efficiently at reduced speeds without sacrificing turbine performance.
Solution Approach 2:
The blade articulation changes the geometric parameters of the blade inlet angle, allowing optimization of the incidence angle parameter throughout the operating range. This parameter adjustment enables the turbine to maintain efficient operation even when operating at reduced speeds with different flow characteristics.
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 solution enhances aerodynamic efficiency, reduces noise and vibration, potentially eliminates the need for active cooling and thermal barrier coatings, increases fuel efficiency, and enables faster and longer flight capabilities for gas turbine engines.
Implementation Method 1
Shape Memory Alloy (SMA) smart material based mechanism
Data Source
AI summary
Conventional gas turbine engines are generally optimized to operate at nearly a fixed speed with fixed blade geometries for the design operating condition. When the operating condition of the engine changes, the flow incidence angles may not be optimum with the blade geometries resulting in reduced off-design performance. By contrast, according to embodiments of the present invention, articulating the pitch angle of turbine blades in coordination with adjustable nozzle vanes improves performance by maintaining flow incidence angles within the optimum range at all operating conditions of a gas turbine engine. Maintaining flow incidence angles within the optimum range can prevent the likelihood of flow separation in the blade passage and also reduce the thermal stresses developed due to aerothermal loads for variable speed gas turbine applications.