Variable Lattice Rotor Shroud for Cabin Air Compressor Stress Management

Solution Overview

Problem

Traditional rotor shrouds for cabin air compressors in aircraft environmental control systems face challenges in managing stress, strain, and energy absorption, leading to inefficiencies and increased failure rates, which affect compression efficiency and safety.

Innovation Solution

A rotor shroud with a variable lattice structure, featuring denser regions for stress, deflection, and energy containment, manufactured using additive manufacturing techniques to optimize mechanical properties and reduce weight while maintaining strength.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Weight of moving object

If traditional solid rotor shroud structure is used, then manufacturing simplicity is maintained, but weight increases and stress distribution becomes inefficient

Engineering Contradiction:

Improverotor shroud weightVSAvoidlattice structure complexity

Core Design Contradiction:

Weight of moving objectVSDevice complexity

Solution Approach 1:

The rotor shroud employs a lattice structure with controlled porosity, creating a network of interconnected struts and voids throughout the component body. This porous architecture reduces material volume and weight while maintaining structural integrity through the distributed lattice framework, directly addressing the weight reduction goal.

Inventive Principle:

Principle #31Porous materials

Solution Approach 2:

The lattice structure implements varying strut densities and configurations in different regions of the rotor shroud, optimizing local mechanical properties where needed. Critical areas receive enhanced structural support through denser lattice arrangements, while non-critical areas utilize sparser configurations to minimize weight, achieving efficient stress distribution.

Inventive Principle:

Principle #3Local quality

2Reliability

If uniform lattice density is used throughout the rotor shroud, then manufacturing simplicity is maintained, but stress management and energy containment become inefficient

Engineering Contradiction:

Improvestress management capabilityVSAvoidvariable lattice structure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The lattice structure implements varying strut densities and configurations in different regions of the rotor shroud, optimizing local mechanical properties where needed. Critical areas receive enhanced structural support through denser lattice arrangements, while non-critical areas utilize sparser configurations to minimize weight, achieving efficient stress distribution.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The lattice structure varies key geometric parameters including strut diameter, strut spacing, and cell size across different regions of the rotor shroud. These parameter changes allow optimization of stress management and energy containment in high-risk areas while reducing material usage in less critical zones, enhancing overall reliability.

Inventive Principle:

Principle #35Parameter changes

3Strength

If denser lattice structure is used in stress and deflection regions, then mechanical strength improves, but manufacturing complexity increases

Engineering Contradiction:

Improvemechanical strength in critical regionsVSAvoidadditive manufacturing complexity

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The lattice structure varies key geometric parameters including strut diameter, strut spacing, and cell size across different regions of the rotor shroud. These parameter changes allow optimization of stress management and energy containment in high-risk areas while reducing material usage in less critical zones, enhancing overall reliability.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The lattice structure implements varying strut densities and configurations in different regions of the rotor shroud, optimizing local mechanical properties where needed. Critical areas receive enhanced structural support through denser lattice arrangements, while non-critical areas utilize sparser configurations to minimize weight, achieving efficient stress distribution.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS11773746B2Turbomachinery rotor shroud with variable lattice densities

Publication Date: 2023.10.03 HAMILTON SUNDSTRAND CORP

AI summary

A rotor shroud for a rotary machine in a cabin air compressor includes a disk portion centered on a central axis of the rotor shroud, a frustoconical portion extending from the disk portion, a flared portion extending from the frustoconical portion, and a variable lattice structure in an interior of the rotor shroud. The variable lattice structure includes a first region of the rotor shroud having a first lattice structure and a second region of the rotor shroud having a second lattice structure. The second lattice structure of the second region is denser than the first lattice structure of the first region. The second region is a deflection region, a stress region, or an energy containment region of the rotor shroud.