Segmented Fan Assembly for Rotor Hub Cooling

Solution Overview

Problem

The fabrication, installation, and maintenance of fan assemblies in dynamoelectric machines are complex, time-consuming, and costly due to the need for welding or riveting of components, which can lead to stress fractures and increased system stoppage time.

Innovation Solution

A segmented fan assembly comprising independently fastened fan assembly elements that form a substantially continuous body around a rotor hub, allowing for easier installation and maintenance, with each element including an axially inner shroud segment, fan blades, and an axially outer shroud segment, and optionally a shroud ring for stabilization.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If components are welded together to decrease fabrication time, then fabrication time is reduced, but stress fractures and fatigue occur at the weld fillet

Engineering Contradiction:

Improvefabrication timeVSAvoidstress fractures and fatigue

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The fan assembly is divided into multiple independently replaceable segments (first shroud segment, second shroud segment, fan blades) that can be assembled without welding or riveting. These segments are connected through interference fits and geometric features that allow quick assembly while avoiding stress concentrations at joints.

Inventive Principle:

Principle #1Segmentation

2Reliability

If components are riveted together to increase durability, then durability is improved, but fabrication time significantly increases

Engineering Contradiction:

ImprovedurabilityVSAvoidfabrication time

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The fan assembly is divided into multiple independently replaceable segments (first shroud segment, second shroud segment, fan blades) that can be assembled without welding or riveting. These segments are connected through interference fits and geometric features that allow quick assembly while avoiding stress concentrations at joints.

Inventive Principle:

Principle #1Segmentation

3Ease of repair

If fan assembly elements are segmented to enable individual installation and removal, then maintenance time is reduced, but device complexity increases

Engineering Contradiction:

Improvemaintenance timeVSAvoidassembly structure

Core Design Contradiction:

Ease of repairVSDevice complexity

Solution Approach 1:

The fan assembly is divided into multiple independently replaceable segments (first shroud segment, second shroud segment, fan blades) that can be assembled without welding or riveting. These segments are connected through interference fits and geometric features that allow quick assembly while avoiding stress concentrations at joints.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Multiple functional components (shroud segments, fan blades, sealing features, alignment features) are integrated into unified fan assembly elements that operate together as a complete replaceable unit, simplifying maintenance while maintaining functional complexity.

Inventive Principle:

Principle #5Merging (Combining)

Data Source

PatentUS8998588B2Segmented fan assembly

Publication Date: 2015.04.07 GE INFRASTRUCTURE TECH LLC

AI summary

Systems and devices for thermodynamically regulating portions of a dynamoelectric machine are disclosed. In one embodiment, a fan assembly element includes: an axially inner shroud segment configured to form a portion of an annular assembly about a rotor of a dynamoelectric machine, wherein the axially inner shroud segment includes a rotor hub interface configured to physically connect to a complementary portion of a rotor hub; a set of fan blades physically connected to and extending axially from a face of the axially inner shroud segment; and an axially outer shroud segment physically connected to the set of fan blades.