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. Student works
  4. Controlling oscillations in spectral schemes using Artificial Neural Networks
 
Loading...
Thumbnail Image
master thesis

Controlling oscillations in spectral schemes using Artificial Neural Networks

Schwander, Lukas  
September 14, 2020

Global Fourier spectral methods are excellent tools to solve conserva- tion laws. They enable fast convergence rates and highly accurate solutions. However, being high-order methods, they suffer from the Gibbs phenomenon, which leads to spurious numerical oscillations in the vicinity of discontinuities. This can have a detrimental effect on the solution quality and lead to unphysical results. While local approxima- tion techniques allow for local limiting or reconstruction, there are no such possibilities for global methods. This thesis proposes a neural net- work based method that adds artificial viscosity around discontinuities of the solution to the conservation law. This enables the transforma- tion of discontinuities into steep but continuous jumps. Test cases in one and two spatial dimensions as well as systems of conservation laws (Euler equations) are solved. Furthermore, the method is generalized to other global basis approaches on non-uniform grids and reduced ba- sis methods. The proposed method delivers satisfactory results in all test cases. On the one hand, it is able to detect and handle discontinu- ities. On the other hand, it stays highly accurate for smooth data.

  • Files
  • Details
  • Metrics
Type
master thesis
Author(s)
Schwander, Lukas  
Advisors
Ray, Deep  
•
Hesthaven, Jan S.  
•
Pagliantini, Cecilia  
•
Mishra, Siddhartha
Date Issued

2020-09-14

Total of pages

127

Subjects

Conservation law

•

Spectral Methods

•

Global Methods

•

Artificial viscosity

•

Artificial neural networks

Written at

EPFL

EPFL units
MCSS  
Available on Infoscience
September 14, 2020
Use this identifier to reference this record
https://infoscience.epfl.ch/handle/20.500.14299/171672
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