Gas Turbine Rotor Blade Cooling Circuit Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gas turbine engine rotor blade cooling systems are inefficient due to manufacturing constraints that limit the effectiveness of cooling fluid in removing heat from the airfoil walls, particularly in channeling cooling fluid through the center of the cavity rather than targeting the walls effectively.
Innovation Solution
The design incorporates multiple cooling circuits within the airfoil cavity, including a central chamber and impingement chambers, down pass chambers, and flag tip chambers, which facilitate impingement cooling and near-wall cooling, allowing for targeted cooling of specific areas such as the leading edge, pressure side, and suction side, and utilize advanced fabrication techniques to overcome manufacturing limitations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If cooling fluid is channeled through the center of the cavity, then the cooling circuit is simple to manufacture, but the cooling effectiveness is reduced because the fluid is ineffective in removing heat from the walls of the airfoil
Solution Approach 1:
The cooling cavity is segmented into multiple distinct cooling circuits (first cooling circuit with first cooling passages, second cooling circuit with second cooling passages) that target different regions of the airfoil. This segmentation allows each circuit to be optimized for its specific cooling zone while maintaining manufacturability through modular passage designs.
Solution Approach 2:
Different cooling circuits are designed with different passage configurations tailored to specific local cooling requirements. The first cooling passages are optimized for cooling certain airfoil surfaces while the second cooling passages target other regions, ensuring that each area receives appropriate cooling intensity and fluid flow patterns.
2Reliability
If impingement inserts are used to channel cooling fluid through impingement jet arrays, then cooling of the leading edge is improved, but manufacturing complexity increases
Solution Approach 1:
The impingement inserts are designed as separate, removable components that can be extracted from the cooling circuit. This allows for easier manufacturing, assembly, and maintenance while still providing the beneficial impingement cooling effect on the leading edge when installed.
Solution Approach 2:
The impingement inserts act as intermediary components that mediate between the cooling fluid source and the airfoil leading edge. These inserts create the impingement jet arrays without requiring direct integration of complex cooling passages into the airfoil structure itself, thereby reducing overall manufacturing 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
This configuration enhances heat transfer and maintains cooler operating temperatures, extending the lifespan of rotor blades in a cost-effective and reliable manner by ensuring efficient cooling of the airfoil surfaces.
Implementation Method 1
compressor bleed air into a cavity defined between the sidewalls, to convectively cool the sidewalls
Implementation Method 2
impingement inserts channel cooling fluid through impingement jet arrays against the inner surface of the airfoil's leading edge to facilitate cooling the airfoil along the leading edge
Data Source
AI summary
An airfoil for a gas turbine engine includes a first sidewall and a second sidewall coupled together at a leading edge and a trailing edge, such that a cavity is defined therebetween. A plurality of cooling circuits are defined within the cavity. Each cooling circuit channels cooling fluid through at least one cooling chamber to facilitate cooling the airfoil. More specifically, a cascade impingement circuit, a down pass circuit, a flag tip circuit, and a trailing edge circuit are provided. The cascade impingement circuit includes a central chamber and a plurality of impingement chambers.