Repository logo

Infoscience

  • English
  • French
Log In
Logo EPFL, École polytechnique fédérale de Lausanne

Infoscience

  • English
  • French
Log In
  1. Home
  2. Academic and Research Output
  3. EPFL thesis
  4. Empowering turbocompressor design with AI: a unified approach to robustness and all-at-once optimization
 
doctoral thesis

Empowering turbocompressor design with AI: a unified approach to robustness and all-at-once optimization

Massoudi, Soheyl  
2024

Achieving robustness in engineering design is crucial for systems such as gas-bearing supported turbocompressors used in heat pumps and fuel cells, where precision affects efficiency and stability. Traditional design methods often optimize for nominal conditions rather than real-world variabilities, largely due to the extensive computational resources required for accurate modeling. This thesis introduces an innovative, automated, AI-based design framework for all-at-once optimization that addresses these challenges more effectively.

The study integrates ensemble artificial neural networks (EANNs) with the Non-Sorted Genetic Algorithm-III (NSGA-III) for comprehensive multidisciplinary design optimization (MDO). This integration accurately models interdependencies among subsystems like bearings, rotors, and impellers and was validated against high-fidelity models, achieving significant computational speed enhancements and real-time simulation capabilities.

The EANNs improved computational speeds by four orders of magnitude, integrating robustness metrics like hypervolume and signal-to-noise ratio directly into the optimization objectives. This approach achieved manufacturing tolerances as large as ±8 micrometers for herringbone grooved journal bearings, enhancing the feasible region for rotor stability by 78% against manufacturing deviations.

Experiments validated the surrogate models' accuracy, extending the EANNs' application to spiral groove thrust bearings and axial dynamics, culminating in a holistic, robust optimization of compressor systems ranging from 1kW to 8kW. The designs showed efficiencies exceeding 82% in higher-power applications and pinpointed an optimal robustness at 3kW.

The thesis led to the ARMID (Automated Robust Modular Integrated Design) framework, integrating surrogate modeling, optimization and real-time simulation tools with an automated 3D CAD generation tool (ParaturboCAD), producing over a thousand CAD models available in STEP and STL formats. This framework enhances the accessibility, robustness, and efficiency of high-precision systems, significantly advancing the field of robust multidisciplinary design optimization.

  • Files
  • Details
  • Metrics
Type
doctoral thesis
DOI
10.5075/epfl-thesis-10785
Author(s)
Massoudi, Soheyl  
Advisors
Schiffmann, Jürg Alexander  
Jury

Prof. Drazen Dujic (président) ; Prof. Jürg Alexander Schiffmann (directeur de thèse) ; Prof. Olga Fink, Prof. Tobias Eifler, Prof. Wei Chen (rapporteurs)

Date Issued

2024

Publisher

EPFL

Publisher place

Lausanne

Public defense year

2024-11-15

Thesis number

10785

Total of pages

310

Subjects

Artificial Intelligence

•

Turbocompressor Design

•

Robust Optimization

•

Surrogate Modeling

•

Multidisciplinary Design Optimization

•

Constrained Multi-Objective Optimization

•

Evolutionary Algorithm

•

NSGA-III

•

Gas Bearings

•

Manufacturing Deviations

EPFL units
LAMD  
Faculty
STI  
School
IGM  
Doctoral School
EDEY  
Available on Infoscience
November 5, 2024
Use this identifier to reference this record
https://infoscience.epfl.ch/handle/20.500.14299/241837
Logo EPFL, École polytechnique fédérale de Lausanne
  • Contact
  • infoscience@epfl.ch

  • Follow us on Facebook
  • Follow us on Instagram
  • Follow us on LinkedIn
  • Follow us on X
  • Follow us on Youtube
AccessibilityLegal noticePrivacy policyCookie settingsEnd User AgreementGet helpFeedback

Infoscience is a service managed and provided by the Library and IT Services of EPFL. © EPFL, tous droits réservés