Rotatable Support Arch for Gas Turbine Spool Torque Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional spool support structures in gas turbine engines face challenges in accommodating the torque and stress generated by the angular momentum of high and low pressure spools, leading to increased weight and cost due to the need for a torque box to manage these loads.
Innovation Solution
A support arch is introduced that rotates at an angular velocity between the high and low pressure spools, allowing the torque from both spools to be transferred to a stationary structural frame, reducing the stress on the frame and enabling a smaller, lighter torque box by distributing the load effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a stationary support frame with bearing is used to support the spools, then the spool rotation is facilitated and load path is provided, but the torque box structure adds to the weight and cost of the engine
Solution Approach 1:
The support arch is made rotatable about the longitudinal axis, allowing it to rotate at an angular velocity between the high and low pressure spools. This dynamic configuration enables the support arch to absorb and distribute torque dynamically, reducing the torque transmission to the stationary support frame and allowing for a lighter torque box structure while maintaining reliable spool support.
2Strength
If a torque box structure is used to accommodate the stress from spool torque, then the structural strength is sufficient, but the device complexity and cost increase
Solution Approach 1:
The rotatable support arch acts as an intermediary element between the spools and the stationary support frame. It mediates the torque transmission by rotating at an intermediate angular velocity, thereby reducing the torque load that must be accommodated by the torque box structure. This intermediary mechanism maintains sufficient structural strength while simplifying the overall device complexity.
3Force
If the support arch rotates at an intermediate angular velocity, then the torque transmission to the stationary frame is reduced, but the bearing system complexity increases
Solution Approach 1:
The bearing system is designed to accommodate the rotatable support arch's intermediate angular velocity rotation. By providing appropriate bearings at the distal ends of the support arch, the system enables smooth rotation while managing the increased complexity through proper bearing selection and arrangement, thereby reducing torque transmission to the stationary frame.
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 reduces the torque and stress transmitted to the stationary structural frame, allowing for a more efficient and cost-effective design that can accommodate the loads from both spools independently, potentially reducing the overall weight and cost of the engine.
Implementation Method 1
The angular momentum ('L') of the axial shaft, which is a function of its angular velocity ('ω'), imparts a torque to the frame to which the bearing is mounted.
Implementation Method 2
The bearings facilitate rotation of the spools and provide a load path between the spool and the support frame.
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
A gas turbine engine (10) is provided that includes a low pressure spool (24), a high pressure spool (26), a stationary support frame (32), and at least one support arch (44). The low pressure spool (24) extends between a low pressure compressor (14) and a low pressure turbine (22). The high pressure spool (26) extends between a high pressure compressor (16) and a high pressure turbine (20). The spools (24,26) are rotatable about a center axis (30) of the engine (10). The support arch (44) has a stationary support mount (50) disposed between a low spool mount (46) and a high spool mount (48). The support arch (44) is disposed relative to the spools (24,26) and the stationary support frame (32) so that a load from each spool (24,26) caused by the rotation of that spool (24,26) can be transferred to the stationary support frame (32) through the support arch (44). The support arch (44) can freely rotate about the center axis (30) of the engine (10) relative to the spools (24,26) and the stationary structural frame (32).