SNIC SUPR
Numerical simulations of water jet pumps, transients in hydraulic turbines, vibrations in fan blades, and tidal power farms
Dnr:

SNIC 2018/3-678

Type:

SNIC Medium Compute

Principal Investigator:

Håkan Nilsson

Affiliation:

Chalmers tekniska högskola

Start Date:

2019-01-01

End Date:

2020-01-01

Primary Classification:

20306: Fluid Mechanics and Acoustics

Allocation

Abstract

This project will be used in four (4) activities: 1: LES of water jet pumps 2: Transients in hydraulic turbines 3: Vibrations of electric generator fan blades 4: Tidal power farms 1: Water jets are used for propulsion of high-speed ships. It is of great importance to improve the efficiency of the pumps. We are doing LES simulations of the rotor-stator interaction, with a focus on tip clearance flow. An aim for the future is to include cavitation modelling. Such methods require a lot of computational resources. 2: Transients between different operating conditions in hydraulic turbines require a detailed resolution of the flow details, using rotor-stator-interaction, adjustable blade angles, and advanced turbulence modeling. Very long time scales need to be included, related to those of the transient processes. Therefore there is a need for a substantial amount of computational resources. 3: The fan blades in electric generators vibrate due to flow unsteadiness and may eventually break, causing great damages to the machines. We will use LES and Fluid-Structure-Interaction methodologies to study the physical processes of the fan blade vibrations. That requires excessive computational meshes, and thus a substantial amount of computational resources. The FSI simulations involve simulations in both solid and fluid regions, and the coupling between the regions. 4: Tidal power plants are packed in farms. We use LES to investigate the interaction between the power plants due to their wakes, and search for the optimal organization of the farms. The Reynolds number is very large, which requires a high resolution. The flow domain must be large enough to allow the turbulence to develop correctly. The oscillating tidal flow has a very long time scale. All these features give a very high computational demand. We recently had a period of ending projects. The projects described in this proposal are starting up, and will reach full speed during the first half of 2019. The first sub-project has already started, and will run at full speed during spring 2019. For that sub-project it is thus of importance to get access to computational resources a.s.a.p. The second project is about to start, and will start to use the resources in the beginning of spring. The third project will start to use the resources at the end of spring. The fourth project is about to be granted, and a PhD project will be started in the beginning of 2019. There are also some senior generic activities planned related to the fourth project.