E-Machine Stator Spray Manifold for Thermal Limit Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional cooling systems for e-machines are ineffective in managing excessive thermal conditions, limiting the power output of e-machines due to thermal constraints, and are inefficient in circulating cooling fluids to the stator.

Innovation Solution

An e-machine with a housing featuring a cooling fluid inlet and outlet, a rotating group, and a stator, along with a manifold member that includes a plurality of nozzles arranged circumferentially to efficiently direct cooling fluid towards the stator, enhancing heat removal and preventing issues like misting, evaporation, and deposit formation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If conventional cooling systems are used, then the e-machine structure is simple, but the cooling effectiveness is limited and thermal management is insufficient

Engineering Contradiction:
Improvestator temperatureVSAvoidcooling system complexity
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The cooling system is segmented into multiple functional components: a manifold member with multiple nozzles arranged circumferentially, separate cooling fluid pathways, and distributed spray zones. This segmentation allows targeted cooling of different stator regions while maintaining manageable system complexity through modular design

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The cooling system provides localized cooling quality by directing cooling fluid through multiple nozzles at specific locations around the stator circumference. Each nozzle delivers cooling fluid to specific high-heat-generation areas, creating non-uniform local cooling quality that matches the thermal profile of the stator

Inventive Principle:
Principle #3Local quality

2Productivity

If cooling fluid is circulated efficiently, then thermal limits are reduced, but the cooling system complexity increases

Engineering Contradiction:
Improvee-machine power outputVSAvoidcooling system structure
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The manifold member merges multiple cooling fluid pathways into a single integrated component that distributes fluid through multiple nozzles. This consolidation reduces the number of separate pipes and connections needed, achieving efficient cooling fluid circulation while controlling system complexity through functional integration

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The manifold member serves multiple functions simultaneously: it distributes cooling fluid to multiple nozzles, structures the spray pattern, and positions cooling elements around the stator. This multi-functionality allows efficient thermal management without proportionally increasing system complexity

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Loss of energy

If cooling fluid is sprayed directly at the stator, then heat removal is improved, but misting, evaporation, and deposit formation occur

Engineering Contradiction:
Improveheat removal efficiencyVSAvoidmisting and evaporation
Core Design Contradiction:
Loss of energyVSObject-generated harmful factors

Solution Approach 1:

The nozzle design changes parameters of the cooling fluid spray including droplet size distribution, spray angle, and fluid velocity. By optimizing these parameters, the system achieves effective heat removal through controlled condensation and film formation on the stator while minimizing harmful misting and evaporation losses

Inventive Principle:
Principle #35Parameter changes

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 described cooling system effectively delivers cooling fluid to the stator, improving e-machine performance by reducing thermal limitations and maintaining efficient operation, while also being manufacturable in an efficient and cost-effective manner.

Implementation Method 1

The plurality of nozzles is in fluid communication with the cooling fluid inlet to receive a cooling fluid therefrom, the plurality of nozzles in an arrangement about the axis of rotation and generally toward the stator, the arrangement of the plurality of nozzles directed generally in a circumferential direction with respect to the axis of rotation from the cooling fluid inlet to the cooling fluid outlet

Methodology Applied
Scientific EffectConvection: Convection

Implementation Method 2

preventing issues like misting, evaporation, and deposit formation

Methodology Applied
Scientific EffectEvaporation: Evaporation

Data Source

PatentEP4300778A1E-machine with a cooling system including manifold member for spray of stator cooling fluid
Publication Date: 2024.01.03 GARRETT TRANSPORTATION I INC
  • EP4300778A1 patent drawingFigure 1
  • EP4300778A1 patent drawingFigure 2
  • EP4300778A1 patent drawingFigure 3

AI summary

An e-machine includes a housing with a cooling fluid inlet and a cooling fluid outlet. The e-machine includes a rotating group supported for rotation about an axis of rotation within the housing. The cooling fluid inlet and the cooling fluid outlet are disposed on opposite sides of the axis of rotation. The e-machine includes a stator disposed within the housing. The e-machine includes a plurality of nozzles in fluid communication with the cooling fluid inlet to receive a cooling fluid therefrom. The plurality of nozzles are arranged about the axis of rotation and generally toward the stator. The arrangement of the plurality of nozzles is directed generally in a circumferential direction with respect to the axis of rotation from the cooling fluid inlet to the cooling fluid outlet.