Film Cooling Riblet Surface Layout for Vortex Loss Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current cooling methods for turbine engines, such as effusion cooling, suffer from inefficiencies due to the loss of cooling fluid film caused by counter-rotating vortices, leading to higher temperatures and potential material issues, and existing solutions like shaped conduits are costly to implement.
Innovation Solution
The use of a member with an array of conduits and riblets, where the riblets extend in the primary flow direction and intersect exit ports, combined with conical conduit shapes and overlapping conduit rows, to enhance film cooling persistence and reduce vortex-induced fluid loss.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If effusion cooling is used to cool turbine engine components, then cooling is provided to combat high temperatures, but cooling fluid film is lost due to counter-rotating vortices reducing cooling efficiency
Solution Approach 1:
The cooling surface is segmented into multiple regions by forming riblets that divide the flow path. These riblets create multiple smaller flow channels that disrupt the formation of large counter-rotating vortices, thereby reducing cooling fluid film loss and improving cooling efficiency.
Solution Approach 2:
Riblets are introduced as intermediary structures between the cooling fluid and the hot surface. These riblets act as mediators that modify the flow characteristics by creating controlled turbulence and preventing vortex-induced film loss, thereby enhancing the cooling process.
2Loss of energy
If shaped conduits are used to improve film cooling, then cooling efficiency is enhanced, but manufacturing cost increases significantly
Solution Approach 1:
Instead of using complex shaped conduits, the solution segments the cooling surface with simple riblet structures. These riblets can be formed using conventional machining or additive manufacturing techniques, significantly reducing manufacturing cost while achieving the vortex-reduction effect needed to improve film cooling efficiency.
Solution Approach 2:
The riblet structures are simple, cost-effective features that can be integrated into the cooling component design without requiring expensive specialized conduit shapes. They provide an economical alternative to complex shaped conduits while achieving similar or better cooling performance.
3Productivity
If riblets are added to the cooling surface, then vortex-induced fluid loss is reduced and cooling efficiency improves, but device complexity increases
Solution Approach 1:
The cooling surface is divided into segmented regions by riblets, creating a structured flow pattern that reduces vortex formation. This segmentation approach improves cooling efficiency while maintaining relatively simple geometry that can be integrated into existing cooling component designs.
Solution Approach 2:
The riblet structures serve multiple functions: they disrupt counter-rotating vortices, enhance cooling fluid film attachment to the surface, and can be integrated with various cooling conduit arrangements. This multi-functionality improves cooling efficiency without requiring separate specialized components.
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 temperature of the primary surface by 50 degrees Fahrenheit compared to ribless designs, improving cooling efficiency and system performance while being more cost-effective.
Implementation Method 1
loss of cooling fluid film caused by counter-rotating vortices
Implementation Method 2
film cooling persistence
Implementation Method 3
array of conduits that extend from an entrance port at the second major surface to an exit port at the first major surface
Data Source
AI summary
A member may have a first major surface and a second major surface. The first major surface may define a plurality of riblets that may extend in the direction of a primary flow. The member may form an array of conduits that extend from an entrance port at the second major surface to an exit port at the first major surface. Each of the exit ports may intersect two or more riblets. Each of the exit ports may intersect a riblet that intersect another of the exit ports.