Turbomachine Rotor Cooling for Blade Tip Clearance Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Turbomachines face efficiency losses due to blade tip clearances, which allow combustion gases to leak, leading to reduced performance and efficiency.
Innovation Solution
A system and method that control axial displacement of turbomachine components using cooled compressed air to reduce thermal expansion, with a control system that selectively directs cooled air to the rotor to maintain contact between turbine blades and the stator, thereby minimizing blade tip clearances.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If blade tip clearance is reduced to minimize gas leakage, then turbomachine efficiency is improved, but thermal expansion causes axial displacement increasing clearance
Solution Approach 1:
The patent changes the thermal parameter (temperature) of the rotor by introducing cooled compressed air through cooling channels. This actively controls the rotor's thermal state to compensate for thermal expansion effects, maintaining optimal blade tip clearance despite temperature variations during operation
Solution Approach 2:
The system incorporates sensors to detect blade tip clearance and axial displacement, feeding this information back to the control system. The controller then adjusts the flow of cooled air through the cooling channels to maintain desired clearance, creating a closed-loop feedback control mechanism
2Stability of the object's composition
If cooled compressed air is directed to the rotor to reduce thermal expansion, then axial displacement is controlled, but device complexity increases
Solution Approach 1:
The compressed air system serves multiple functions: it provides cooling to reduce thermal expansion, acts as a control medium for axial displacement, and can be regulated to adapt to different operating conditions. This multi-functionality reduces the need for separate dedicated cooling and control systems
Solution Approach 2:
The system uses the turbomachine's own compressed air output as the cooling medium, rather than requiring an external cooling system. The compressed air is diverted through cooling channels to cool the rotor, making the system self-sufficient and reducing external complexity
3Productivity
If blade tip clearance is eliminated to improve efficiency, then gas leakage is minimized, but manufacturing precision requirements increase
Solution Approach 1:
Instead of relying solely on fixed manufacturing precision, the patent introduces a dynamic control system that actively adjusts blade tip clearance during operation. The cooling channels and control system allow real-time modification of rotor position to maintain optimal clearance under varying thermal and operational conditions
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 approach effectively reduces or eliminates blade tip clearances, enhancing turbomachine efficiency by minimizing gas leakage and optimizing thermal expansion between rotor and stator components.
Implementation Method 1
direct the cooled compressed air adjacent to the turbomachine rotor to reduce thermal expansion and/or axial displacement of the turbomachine rotor
Implementation Method 2
diverting a first portion of compressed air to a heat exchanger during certain stages of operation of the turbomachine and cooling the first portion of compressed air via the heat exchanger
Data Source
AI summary
A system includes a turbomachine rotor having a shaft and turbomachine blades coupled to the shaft. The system also includes a turbomachine stator having a shroud surrounding the turbomachine blades of the turbomachine rotor. Further, the system includes a cooling channel having at least a first portion of the cooling channel extending upstream of a final stage of a compressor of the system, where the cooling channel is configured to receive cooled compressed air from the compressor and direct the cooled compressed air adjacent to the turbomachine rotor to reduce thermal expansion and/or axial displacement of the turbomachine rotor.