Turbine Blade Tip Plenum Cooling for Trailing-Edge Oxidation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing configurations for cooling turbine blade tips are inadequate, leading to thermal induced degradation and oxidation, particularly near the trailing edge, and backflow of hot combustion gas due to insufficient feed pressure.
Innovation Solution
A method of modifying a turbine blade by removing a section from the leading edge to the trailing edge and replacing it with a section that defines a plenum connected to forward tip cooling apertures, reducing the number of tip cooling apertures connected to the third leg compared to the initial form.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If existing tip cooling configurations are used, then the turbine blade can operate, but inadequate cooling occurs near the trailing edge and backflow of hot combustion gas occurs
Solution Approach 1:
The tip cooling system is segmented into multiple independent aperture groups: forward tip cooling apertures supplied by a plenum, and reduced number of tip cooling apertures supplied by the third leg. This segmentation allows different regions of the blade tip to receive cooling air from different sources, ensuring adequate cooling coverage including the previously problematic trailing edge area.
Solution Approach 2:
A plenum is introduced as an intermediary component between the cooling air supply and the forward tip cooling apertures. The plenum acts as a distribution chamber that ensures uniform cooling air flow to the forward tip region, preventing both inadequate cooling and backflow of hot combustion gas in the tip area.
2Reliability
If more tip cooling apertures are used, then cooling coverage improves, but manufacturing complexity and aperture density increase
Solution Approach 1:
Instead of uniformly distributing many small apertures across the entire tip, the system segments cooling apertures into two distinct groups with different supply sources. The forward tip cooling apertures are supplied by the plenum, while fewer apertures near the trailing edge are supplied by the third leg, simplifying the overall aperture configuration while maintaining comprehensive cooling coverage.
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 modified turbine blade achieves improved cooling of the blade tip, reducing thermal degradation and oxidation, and preventing backflow of hot gases by optimizing the airflow through the plenum and reduced apertures.
Implementation Method 1
Cooling of the turbine component may be provided by the use of compressed air that flows through various passages within, and exiting, the turbine component
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A turbine blade (100, 100') includes a blade tip (106) defining pressure side cooling apertures. The turbine blade (100, 100') defines a serpentine cooling passage having a first, second, and third legs, and first and second junction portions. The first leg (268) extends radially and is connected to the second leg (270) by the first junction portion proximate the blade tip (106). The second leg (270) extends radially between the first and second junction portions. The second junction portion connects the second leg (270) to the third leg which extends radially toward the blade tip (106) and is connected to a trailing edge cooling aperture to exhaust the gas to an exterior of the turbine blade (100, 100'). The turbine blade (100, 100') defines a plenum (410) connected to the first junction portion. At least one tip cooling aperture connects to the plenum (410) and is radially outward of the third leg and axially aftward of at least a portion of the third leg.