Nested Oil Distributor Layout for Aircraft Reduction Gear Lubrication
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing lubrication systems for mechanical reduction gears in turbine engines, particularly in aircraft, face inefficiencies due to temperature differences between lubricating oils, where hotter oils used for bearings can heat up colder oils used for gearings, potentially reducing lubrication performance.
Innovation Solution
A lubricating oil distributor with two independent oil circuits of different temperatures, where one circuit is thermally insulated within the other to prevent overheating of the colder oil, ensuring optimal lubrication performance by minimizing heat transfer between oils.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single lubrication circuit is used for both gearings and bearings, then the device complexity is reduced, but the lubrication performance deteriorates due to temperature cross-contamination between circuits
Solution Approach 1:
The distributor channels are arranged in a nested configuration where the first annular channel is positioned concentrically within the second annular channel. This nesting provides thermal insulation between the two lubrication circuits, preventing heat transfer from the bearing lubrication oil to the gearing lubrication oil, while maintaining a unified single-piece distributor structure.
2Loss of energy
If hot oil from bearing lubrication contacts cold oil in gearing lubrication, then the loss of energy increases due to unwanted heat transfer, but the lubrication performance of cold oil deteriorates
Solution Approach 1:
The nested arrangement of annular channels creates a thermal barrier that isolates the cold gearing lubrication oil from the hot bearing lubrication oil, preventing energy loss through unwanted heat transfer and maintaining the optimal temperature and lubrication performance of the cold oil.
Solution Approach 2:
The wall structure separating the two annular channels acts as a thermal intermediary or barrier, controlling and limiting heat transfer between the two lubrication circuits. This intermediary structure prevents direct thermal interaction while allowing both circuits to function independently.
3Ease of manufacture
If a single-part distributor is used, then the ease of manufacture is improved, but the ability to provide thermal insulation between circuits is limited
Solution Approach 1:
The nested annular channel configuration can be manufactured as a single integrated part using conventional machining or additive manufacturing processes. The concentric arrangement inherently provides thermal insulation through the material wall separating the channels, achieving both manufacturing simplicity and thermal isolation.
Solution Approach 2:
The solution moves from considering thermal insulation as a separate component function to utilizing the spatial arrangement in the radial dimension. By positioning channels at different radial positions with insulating material between them, thermal isolation is achieved through dimensional separation rather than through additional insulating 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 solution effectively maintains the optimal temperature of lubricating oils, enhancing the lubrication performance and reducing the risk of overheating, thereby improving the efficiency and longevity of the reduction gear components.
Implementation Method 1
The invention proposes overcoming this problem by thermally insulating at least a part of the circuit comprising the colder oil. This is possible by nesting one section of the oil chambers in the other. This configuration leads to an "inner" chamber that is thermally insulated by an "outer" chamber.
Implementation Method 2
During operations, the oil that has lubricated these parts is projected radially outwards by centrifugal forces and has a temperature greater than its initial temperature
Implementation Method 3
This cold oil is thus likely to be heated by the oil that served to lubricate the reduction gear, which could negatively impact the lubricating performance of this colder oil
Data Source
AI summary
Lubricating oil distributor for a mechanical reduction gear of a turbine engine, in particular of an aircraft, wherein it has a general annular shape around an axis X and is formed of a single part, the distributor including first and second independent oil circuits, the first oil circuit including a first oil inlet connected by a first annular chamber to several oil outlets, and the second oil circuit including a second oil inlet connected by a second annular chamber to several oil outlets, the first chamber including a section that is at least partially nested in a section of the second chamber.