Lattice Boltzmann Methods for Hydraulic Turbomachines

You are cordially invited to attend the PhD Dissertation Defence of David Roos Launchbury on Monday 19 May 2025 at 13:00 in room D1.14.

Abstract:
In the field of energy production, hydraulic turbomachines such as turbines and pump-turbines often operate under part-load conditions, where the flow is characterized by highly complex unsteady behaviour. The numerical simulation of such flows is challenging, as many of the transient phenomena are dominated by turbulent effects. Traditional Reynolds-averaged Navier-Stokes (RANS) methods struggle with such flows due to their reliance on turbulence models, while large eddy simulations (LES) are computationally prohibitive for industrial applications. The lattice Boltzmann method (LBM) offers a promising alternative, with its high parallelizability and potential for accurate simulations of turbulent flows, but is largely absent in the investigations of unsteady flows in hydraulic turbomachines. This work develops a CFD solver based on the entropic multi-relaxation time LBM to efficiently simulate turbulent flows in rotating machines. The solver, TurboLaB, is designed to investigate unsteady flow phenomena in off-design conditions within an industrially acceptable timeframe. The thesis covers the governing equations, solver implementation, verification, and validation through academic and industrial test cases. The results demonstrate the potential of LBM for turbomachinery simulations, providing a foundation for further research in this domain.

Dissertation Committee:
- Prof. Rolf Krause, Università della Svizzera italiana, Switzerland (Research Advisor)
- Prof. Ernesto Casartelli, Hochschule Luzern, Switzerland (Research co-Advisor)
- Prof. Luca Mangani, Hochschule Luzern, Switzerland (Research co-Advisor)
- Prof. Cesare Alippi, Università della Svizzera italiana, Switzerland (Internal Member)
- Prof. Michael Multerer, Università della Svizzera italiana, Switzerland (Internal Member)
- Prof. Dorschner Dorschner, ETH Zurich/NVIDIA (External Member)
- Prof. Ilya Karlin, ETH Zurich (External Member)