Nut Continuous Annular Surface Reduces Windage Loss
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In gas turbines, windage loss occurs due to working fluid flowing into the cavity and generating swirl, which decreases efficiency as it interacts with the nut and bolts, leading to increased ambient temperature.
Innovation Solution
A nut configuration with a continuous annular surface formed by cooperating cover surfaces of multiple nuts reduces fluid flow between them, minimizing windage loss by design features such as a plate-like cover portion and screw holes, preventing fluid ingress and centrifugal force effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a seal member is disposed in the cavity to prevent working fluid flow, then windage loss is reduced, but some working fluid still flows into the space through the seal member generating swirl and contact with the nut
Solution Approach 1:
The invention merges the sealing function with the nut structure itself by forming a continuous annular surface from the cover surfaces of multiple nuts. This integration creates an effective barrier against working fluid flow without requiring separate seal members, thereby reducing windage loss while maintaining sealing reliability.
Solution Approach 2:
The continuous annular sealing surface is segmented into multiple discrete nut components distributed circumferentially. Each nut contributes a cover surface that, when combined with adjacent nuts, forms the complete sealing barrier. This segmentation allows for practical assembly and maintenance while achieving the overall sealing effect.
2Ease of manufacture
If the nut structure is simplified to reduce manufacturing complexity, then production cost decreases, but the ability to form a continuous annular surface for reducing fluid flow may be compromised
Solution Approach 1:
The nut is designed with a cover surface that serves dual functions: maintaining the structural integrity of the fastening assembly and forming part of the continuous annular sealing surface. This multi-functionality eliminates the need for separate sealing components, simplifying manufacturing while effectively reducing windage loss.
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 reduced fluid flow between nuts decreases windage loss, enhancing gas turbine efficiency by minimizing fluid interaction and preventing nut loosening due to centrifugal forces.
Implementation Method 1
the amount of fluid flowing in between the nuts when the rotary member rotates is reduced by the annular surface formed by the plurality of nuts
Implementation Method 2
the weight of the nut can be reduced by forming the section that constitutes the first cover surface as a plate
Implementation Method 3
the fluid around the nut can flow smoothly. As a result, windage loss can be further reduced
Implementation Method 4
turning up of the cover surface due to centrifugal force that acts upon the cover surface when the rotary member rotates can be prevented
Data Source
AI summary
Provided is a nut (12) configured to engage with an end portion on a first side of each of bolts (11) that pass through a plurality of rotary members in an axial direction at a plurality of locations in a circumferential direction having an axis (A) as the center thereof, the plurality of rotary members being stacked along the axial direction in which the axis (A) extends, the nut (12) comprising a first cover surface (35), which is the surface opposite a surface that faces a second side opposite the first side of the bolts (11), wherein, among all surfaces of the nut, at least the first cover surface (35) cooperates with the first cover surface (35) of another nut (12) to form a continuous annular surface with the axis (A) as the center thereof.