Metal Foam Diffuser Reduces Windage in Turbine Sump
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional lubrication systems in high-speed rotating structures, such as turbine engines, face challenges in efficiently scavenging lubricant due to windage and gravity changes, leading to lubricant churn and overheating, especially in airborne applications where gravity's effect is compromised.
Innovation Solution
A lubrication scavenge system incorporating an open cell metal foam body that encircles the rotating structure to minimize windage and direct lubricant flow, with a sump housing that receives and directs the lubricant, defining paths for lubricant movement and reducing windage generation by minimizing the distance between the structure and the foam body.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional sump is used to collect lubricant in high-speed rotating structures, then lubricant collection is achieved, but windage causes lubricant churn and overheating
Solution Approach 1:
The patent employs an open cell metal foam body as a diffuser in the lubricant sump. This porous material creates a large surface area with numerous small cells that break up lubricant flow patterns, reducing windage-induced churn and heat generation while maintaining effective lubricant collection and circulation.
Solution Approach 2:
The metal foam diffuser acts as an intermediary between the lubricant and the sump environment. It mediates the interaction by transforming the lubricant flow from direct exposure to windage into a distributed flow through porous cells, thereby reducing harmful windage effects while maintaining lubricant functionality.
2Ease of operation
If gravity-dependent lubricant drainage is used, then lubricant returns to the sump, but changing attitude in airborne applications negates gravity effects
Solution Approach 1:
The metal foam diffuser enables the lubrication system to be self-regulating. The porous structure allows lubricant to be drawn into and distributed through the foam cells by capillary action and pressure differentials created during rotation, eliminating dependence on gravity for effective lubricant return and distribution regardless of system attitude.
Solution Approach 2:
The patent replaces gravity-dependent mechanical drainage with a porous media-based distribution system. The metal foam diffuser uses capillary forces and pressure gradients inherent in porous materials to achieve lubricant flow and distribution independent of gravitational direction, enabling adaptability to various attitudes in airborne applications.
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 system effectively reduces windage and enhances lubricant flow, ensuring quicker removal and preventing overheating, thereby improving the performance and life of lubricated components in high-speed rotating environments.
Implementation Method 1
an open cell metal foam body disposed in the volume and tightly encircling the structure to substantially reduce windage
Implementation Method 2
The open cell metal foam body defines paths of movement for lubricant expelled from the structure
Data Source
AI summary
A lubrication scavenge system is disclosed herein. The lubrication scavenge system includes a structure disposed for high-speed rotation about an axis. The lubrication scavenge system also includes a sump housing with an inwardly-facing surface substantially encircling the structure for receiving and directing lubricant expelled from the structure. A volume is defined between the structure and the inwardly-facing surface. The lubrication scavenge system also includes an open cell metal foam body disposed in the volume and tightly encircling the structure to substantially reduce windage.