Gearbox Lubrication Backup Pump for Windmill Shutdown Conditions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional lubrication systems for turbine engines fail to provide consistent lubrication to gearbox assemblies during in-flight shutdown and windmill conditions, leading to increased wear and potential component failure due to cessation of oil flow.
Innovation Solution
A dual lubrication system with a primary and auxiliary circuit, where a clutch engages the auxiliary supply pump when primary lubricant pressure falls below a threshold, ensuring continuous lubrication by monitoring pressure with a sensor.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single primary lubrication system is used, then the device complexity is reduced, but the reliability of lubrication supply deteriorates during in-flight shutdown and windmill conditions
Solution Approach 1:
The lubrication system is divided into two independent circuits: a primary lubrication circuit and a secondary lubrication circuit. Each circuit has its own pump and can operate independently. The primary circuit uses engine-driven pump while the secondary circuit uses an electrically-driven pump, allowing one to take over if the other fails or becomes inoperative during in-flight shutdown or windmill conditions.
Solution Approach 2:
The system changes the operational parameters of the lubrication circuits based on engine state. During normal operation, the primary circuit is active. During in-flight shutdown or windmill conditions when the engine stops rotating, the system switches to the secondary circuit with the electrically-driven pump to maintain lubrication pressure and flow to critical components.
2Device complexity
If the primary pump is driven by the engine shaft, then the system is simpler and more efficient during normal operation, but the lubrication supply stops when the shaft does not rotate
Solution Approach 1:
The pump system is segmented into two independent pumping mechanisms: an engine-driven pump for normal operation and an electrically-driven pump for backup. This segmentation allows each pump to be optimized for its specific operating condition while ensuring continuous lubrication coverage across all engine states including in-flight shutdown and windmill conditions.
Solution Approach 2:
The control system acts as an intermediary that monitors engine operation and automatically switches between the primary engine-driven pump and the secondary electrically-driven pump. This intermediary function ensures seamless transition and maintains continuous lubrication supply without requiring manual intervention or complex mechanical coupling between the two pump systems.
3Device complexity
If no backup lubrication circuit is provided, then the manufacturing cost and system complexity are lower, but the risk of component failure increases during abnormal operational conditions
Solution Approach 1:
The system incorporates a secondary lubrication circuit with an electrically-driven pump as a pre-prepared backup before any failure occurs. This backup circuit is designed to automatically activate during in-flight shutdown or windmill conditions, providing cushioning protection against lubrication failure and preventing component wear and damage before they can occur.
Solution Approach 2:
The system dynamically changes the operational state of the lubrication circuits based on detected engine conditions. When abnormal conditions such as in-flight shutdown or windmill operation are detected, the control system changes parameters by activating the secondary circuit with the electrically-driven pump, thereby adapting the system to maintain protective lubrication function under all operational scenarios.
Data Source
AI summary
A lubrication system for a turbine engine includes a reservoir that stores a lubricant, a primary lubricant supply circuit including a primary supply pump fluidly coupled to the reservoir, and an auxiliary lubricant supply circuit including an auxiliary supply pump fluidly coupled to the reservoir. A clutch is mechanically coupled to the auxiliary supply pump, and the clutch configured to engage the auxiliary supply pump and a shaft of the turbine engine when activated. The lubrication system further includes a pressure sensor that monitors a lubricant pressure within the primary lubricant supply circuit. When the lubricant pressure within the primary lubricant supply circuit falls below a predetermined lubricant threshold, the clutch is activated to engage the auxiliary supply pump and the shaft of the turbine engine.