Turbine Casing Cooling Plate Radial Contraction for Tip Clearance Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing gas turbines face inefficiencies due to inappropriate tip clearance between the turbine blade and the casing, leading to reduced performance and potential damage from excessive clearance or insufficient clearance.
Innovation Solution
An apparatus with a cooling plate having a unique shape, featuring fins and a ring segment, is installed in the turbine casing to efficiently supply cold air, allowing the cooling plate to contract radially and adjust the tip clearance effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the tip clearance is increased above an acceptable level, then the blade can avoid scratching the inner wall of the turbine casing, but the amount of combustion gas that is not activated and is discharged between the turbine casing and the blade increases, reducing overall efficiency
Solution Approach 1:
The patent applies the dynamics principle by making the cooling plate movable rather than fixed. The cooling plate can be radially moved to adjust the tip clearance dynamically, allowing the system to adapt to different operating conditions. This enables the blade to maintain optimal clearance from the casing while preventing excessive combustion gas discharge, thus resolving the contradiction between damage prevention and energy loss.
Solution Approach 2:
The patent changes the physical state and position parameters of the cooling plate to control tip clearance. By radially moving the cooling plate, the system changes the clearance parameter between the blade and casing, allowing optimization of both blade protection and combustion gas utilization, thereby addressing the contradiction between reliability and energy loss.
2Loss of energy
If the tip clearance decreases below an appropriate level, then the overall efficiency of the gas turbine improves, but the blade may scratch the inner wall of the turbine casing
Solution Approach 1:
The movable cooling plate allows dynamic adjustment of tip clearance to prevent blade scratching while maintaining efficient combustion gas utilization. The system can adapt the clearance based on operating conditions, resolving the contradiction between energy efficiency and blade protection.
Solution Approach 2:
The system incorporates feedback mechanisms to monitor and adjust tip clearance. By continuously monitoring the clearance and providing feedback to the control system, the patent enables real-time adjustment of the cooling plate position to maintain optimal clearance, preventing both blade damage and excessive energy loss.
3Device complexity
If a conventional cooling plate is used, then the structure is simple, but the cooling plate cannot contract sufficiently in the radial direction to control tip clearance effectively
Solution Approach 1:
The cooling plate is segmented into multiple sections with different thermal expansion characteristics. This segmentation allows the cooling plate to contract more effectively in the radial direction when cooled, improving tip clearance control precision while maintaining reasonable structural complexity.
Solution Approach 2:
The cooling plate incorporates local quality variations through fins and different material properties in different regions. The fins increase the surface area for heat dissipation, allowing the cooling plate to contract more uniformly and precisely in the radial direction, thereby improving clearance control without excessive 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 apparatus enables precise control of tip clearance, improving the gas turbine's efficiency and preventing damage by allowing the cooling plate to contract radially, thus maintaining an optimal clearance between the turbine blade and the casing.
Implementation Method 1
a cooling plate installed in a groove, formed in a circumferential direction in the casing, and contracted by cold air supplied thereto
Data Source
AI summary
An apparatus for controlling tip clearance between a turbine casing and a turbine blade is provided. The apparatus for controlling tip clearance includes a casing surrounding the turbine blade, a cooling plate installed in a groove, formed in a circumferential direction in the casing, and contracted by cold air supplied thereto, the cooling plate having at least one fin formed on an outer peripheral surface thereof, and a ring segment mounted radially inside the cooling plate.