Segmented Angel-Wing Seal for Short-Shank Turbomachine Blades
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional angel-wing seal configurations are not suitable for short-shank bucket or blade designs, as they lack sufficient space for double-stacked radially-spaced seal elements, necessitating a flexible seal arrangement for various turbomachine bucket and blade designs.
Innovation Solution
An arcuate cover plate with detachable arcuate angel-wing seal segments, secured via fastening elements, is designed to axially overlie root and shank portions of turbomachine buckets or blades, allowing for customizable sealing configurations and accommodating different materials for temperature compatibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional angel-wing seal configurations are used, then sealing function is provided, but they cannot accommodate short-shank bucket or blade designs due to insufficient space
Solution Approach 1:
The angel-wing seal is divided into multiple radially-spaced seal elements (inner seal element and outer seal element) that can be independently positioned on the cover plate. This segmentation allows the seal to be configured in double-stacked arrangements or other patterns that accommodate limited shank length while maintaining effective sealing functionality.
Solution Approach 2:
The seal elements are arranged in radial directions from the cover plate rather than only axially, utilizing the radial dimension to provide multiple sealing paths. This multi-dimensional arrangement enables effective sealing within the constrained axial space of short-shank designs by distributing seal elements across radial and axial positions.
2Reliability
If double-stacked radially-spaced seal elements are used, then sealing performance is improved, but space requirements increase making them unsuitable for short-shank designs
Solution Approach 1:
The seal is segmented into multiple independent seal elements that can be radially spaced and double-stacked on the cover plate. This segmentation allows the sealing function to be distributed across multiple elements in a compact arrangement, achieving reliable sealing through redundant paths while minimizing the total volume occupied by the seal assembly.
Solution Approach 2:
The inner seal element and outer seal element are nested in a radial configuration around the bucket or blade shank, with each element positioned at different radial distances from the center. This nested arrangement allows multiple sealing elements to occupy overlapping radial and axial spaces efficiently, providing enhanced sealing reliability within limited volume constraints.
3Ease of manufacture
If integral angel-wing seals are cast with the bucket or blade, then manufacturing is simplified, but flexibility for different designs is reduced
Solution Approach 1:
The seal elements are provided as separate components that can be independently manufactured and then assembled to the cover plate using mechanical fastening elements. This segmentation maintains manufacturing simplicity for each component while enabling flexible configuration arrangements (such as double-stacked or radially-spaced patterns) that can be adapted to different bucket and blade designs without requiring new integral castings.
Solution Approach 2:
The cover plate with detachably secured seal elements serves multiple functions: it provides the sealing function through various seal element arrangements, accommodates different bucket and blade designs, and allows for easy modification or replacement of seal elements. This universal configuration can be adapted to various design requirements while using the same basic cover plate structure.
Data Source
AI summary
A cover plate adapted to axially overlie root or shank portions of one or more buckets or blades secured to a turbomachine wheel, includes an arcuate cover plate body adapted to be secured to the turbomachine wheel so as to cover a root portion of at least one of the turbine buckets or blades; and at least one arcuate angel-wing seal segment detachably secured to one side of the arcuate cover plate body.