Variable-Pitch Stator Vane Fins for Compressor Vortex Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Turbomachine compressor stages experience aerodynamic losses due to the formation of vortices at the connection between blades and plates, which affect airflow straightening efficiency.
Innovation Solution
The design incorporates variable-pitch stator blades with radially internal and external plates featuring transverse longitudinal walls with fins that project radially, where each fin's upstream end is offset downstream relative to the blade's leading edge, breaking up vortices and minimizing their formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If conventional stator blades with straight plates are used, then the structure is simple, but vortices form at the connection between blades and plates causing aerodynamic losses
Solution Approach 1:
The transverse longitudinal wall of the plate is segmented by adding fins that project radially between the blade and the plate. These fins divide the continuous wall into multiple sections, disrupting the vortex flow path and reducing aerodynamic losses caused by corner vortices at the blade-plate connection.
Solution Approach 2:
Fins are introduced as intermediary structures between the blade and the plate. These fins act as mediators that intercept and redirect the boundary layer flows, preventing the formation of strong corner vortices while maintaining the structural integrity of the blade assembly.
2Reliability
If fins are added to the transverse longitudinal wall, then vortex formation is reduced, but manufacturing complexity increases
Solution Approach 1:
The fins are integrated directly into the transverse longitudinal wall of the plate, merging the fin structure with the existing plate geometry. This integration reduces the number of separate components and simplifies manufacturing processes compared to adding fins as separate attached elements.
Solution Approach 2:
The fins are positioned specifically at the critical regions where corner vortices form at the connection between the blade and plate. By concentrating the vortex-disrupting features only where needed rather than throughout the entire structure, the manufacturing complexity is minimized while maintaining effectiveness.
3Loss of energy
If the upstream end of fins is offset downstream relative to the leading edge, then vortex breakup is enhanced, but the longitudinal dimension of the plate increases
Solution Approach 1:
The fins are offset downstream relative to the leading edge by a specific distance (at least 30% of the plate longitudinal length) to achieve partial action. This offset positioning provides sufficient downstream distance for the fins to effectively break up and redirect vortex flows without requiring the full plate length, thus avoiding excessive dimensional increases.
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 configuration effectively reduces the formation and amplification of vortices, enhancing airflow straightening and compressor performance by minimizing aerodynamic losses.
Implementation Method 1
The presence of the fins helps to break up the vortices forming at the connection between the blade and each plate
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
The invention proposes a variable-pitch stator vane (14) for a compressor stator (44) of a turbomachine, which extends in a radial longitudinal plane and comprises a radially inner plate (16) and a radially outer plate (18) between which there extends at least one airfoil (12), each plate (16, 18) comprising a transverse longitudinal wall (22) facing the other plate (16, 18), characterized in that said transverse longitudinal wall (22) of at least one plate (16, 18) comprises at least one fin (34) that projects radially toward the other plate (16, 18).