Geared Turbofan Carrier Mounting for Accessory Power Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Turbine engine manufacturers seek to improve thermal, transfer, and propulsive efficiencies, and existing fan drive gear systems for turbofan engines do not effectively address these efficiency improvements while driving accessory components.
Innovation Solution
A fan drive gear system that includes a sun gear driven by an engine shaft, intermediate gears coupled to the sun gear, a ring gear coupled to the intermediate gears, and a carrier supporting the rotation of the intermediate gears, with an accessory component coupled to the carrier, allowing for efficient power transmission and accessory component operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If accessory components are driven by a coupling to an engine shaft, then the accessory components can be powered, but the engine cannot achieve improved thermal, transfer, and propulsive efficiencies
Solution Approach 1:
The fan drive gear system is designed to perform multiple functions: it drives the fan section at a different speed than the turbine while simultaneously powering accessory components through the carrier. This multi-functionality eliminates the need for separate drive systems, thereby improving engine efficiency without proportionally increasing complexity.
Solution Approach 2:
The patent combines the fan drive function and accessory component drive function into a single integrated gear system. The carrier that supports the intermediate gears is coupled to accessory components, merging two previously separate drive functions into one unified system, which improves overall efficiency.
2Productivity
If the fan section rotates at the same speed as the turbine section, then the drive system is simple, but the propulsive efficiency is reduced
Solution Approach 1:
The gear system segments the power transmission path into distinct functional components: sun gear driven by the turbine shaft, intermediate gears on the carrier, and ring gear connected to the fan shaft. This segmentation allows independent speed control of the fan section relative to the turbine section, enabling optimized propulsive efficiency.
Solution Approach 2:
The epicyclic gear system provides dynamic speed ratio adjustment capability, allowing the fan section to rotate at an optimized speed different from the turbine section. The carrier's rotation relative to the sun and ring gears creates variable speed relationships that optimize propulsive efficiency.
3Productivity
If accessory components are mounted to the carrier, then they are efficiently powered, but the mounting complexity increases
Solution Approach 1:
The carrier acts as an intermediary element between the fan drive gear system and the accessory components. It provides a standardized interface for mounting accessories, simplifying the power transmission connection while maintaining manufacturing ease through modular design.
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 fan drive gear system enhances engine efficiency by enabling the fan section to operate at a different speed than the turbine section, while also efficiently powering accessory components like fluid pumps and electric motor/generators, thereby improving overall engine performance.
Implementation Method 1
A speed reduction device such as an epicyclical gear assembly may be utilized to drive the fan section such that the fan section may rotate at a speed different than the turbine section
Data Source
AI summary
A fan drive gear system for a turbine engine includes a sun gear that is configured to be driven by an engine shaft rotatable about an axis. A plurality of intermediate gears are coupled to the sun gear, a ring gear is coupled to the plurality of intermediate gears, and a carrier supports rotation of the plurality of intermediate gears. The carrier includes a gear portion and an accessory component that is coupled to and driven by the gear portion of the carrier.