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Alexander Jaust

Senior analyst IT

Equinor ASA

Biography

I am currently working as software engineer at Equinor ASA .

Before working in Bergen, I was a postdoctoral research in the group of Prof. Miriam Schulte at Stuttgart University at the Institute for Parallel and Distributed Systems (IPVS). Here I am member of the collaborative research center SFB1313 about “Interface-Driven Multi-Field Processes in Porous Media - Flow, Transport and Deformation”. My work within the SFB is concerned with efficient partitioned coupling schemes for porous media applications.

Before working in Stuttgart I obtained a master’s degree in Computational Engineering Science at RWTH Aachen University (Germany). After my master’s I started a PhD at RWTH Aachen University and Hasselt University (Belgium) where I was part of a joint PhD program. During my PhD studies I mainly focused on efficient high-order methods for computational fluid dynamics. I moved to the supercomputing center at KU Leuven where I worked as high-performance computing analyst/consultant for a year before going to Stuttgart.

You can find my current hompage at the Institute for Parallel and Distributed Systems here .

Interests

  • Partitioned coupling methods for porous media applications
  • High-order methods in computational fluid dynamics
  • High-performance computing

Education

  • PhD in Computational Mathematics, 2018

    Hasselt University and RWTH Aachen University

  • MSc in Computational Engineering Science, 2013

    RWTH Aachen University

  • BSc in Computational Engineering Science, 2011

    RWTH Aachen University

Experience

 
 
 
 
 

Senior Analyst IT

Equinor ASA

Oct 2022 – Present Norway
Software developer working on seismic data in the cloud and other geoscientific applications.
 
 
 
 
 

Postdoc

University of Stuttgart

Dec 2018 – Sep 2022 Germany
Postdoctoral researcher at the Institute for Parallel and Distributed Systems in the group of Prof. Dr. Miriam Schulte. I am a member of the SFB1313 and work on partitioned coupling schemes for porous media applications.
 
 
 
 
 

HPC Analyst/consultant

Hasselt University and KU Leuven

Dec 2017 – Nov 2018 Belgium
High-performance computing analyst/consultant supporting users with using the supercomputers at the Flemish supercomputer center (VSC). My tasks ranged from helpdesk support to the implemention of new features as the integration of a JupterHub service running on the supercomputer.
 
 
 
 
 

PhD student

Hasselt University and RWTH Aachen University

Feb 2014 – Oct 2018 Belgium and Germany
PhD student with Prof. Dr. Jochen Schütz (UHasselt) and Prof. Dr. Manuel Torrilhon (RWTH Aachen) where I was part of a joint PhD program. I did research in the field of high-order discretizations for computational fluid dynamics.

Recent & Upcoming Talks

Simulation of interface-coupled porous-medium applications using partitioned coupling methods

Many real-world applications involve interface-coupled processes and porous media. Common examples are the hydromechanical coupling of liquid in a fracture under high pressure and the resulting deformation of the surrounding porous medium or coupled free and porous-medium flow. These examples play an important role in hydraulic simulations or simulations of filters. Moreover, the underlying problems can be split in two non-overlapping subdomains with different physical properties and mathematical models that are separated by a sharp interface. Solving such problems numerically leads to ill-conditioned (linearized) systems of equations if a monolithic solution strategy is used. We circumvent the problem of ill-conditioned system of equations by solving the problems by partitioned black-box methods which are based on the idea of domain decomposition techniques. The individual problems are solved separately in an iterative manner. Suitable values for the coupling condition on the interface ensure that we recover the coupled behavior of the original problem. Additionally, we employ so-called accelerators based on interface quasi-Newton methods for stabilization and acceleration of the iterative coupling process. The black-box nature of the applied coupling method only relies on the data exchanged between the subdomains which simplifies the coupling of different solver (software) packages. We investigate different black-box coupling methods for the mentioned porous-medium applications to show their versatility and to identify suitable accelerator configurations. The presented approach is based on the open-source library preCICE ( www.precice.org ) which, amongst other things, includes functionality to communicate data, to steer the coupling process, and to apply the acceleration to the coupling process.