The influence of wind turbines on local seismic stations, sensitive seismological observatories and gravitational wave observatories is recognised to be of growing importance as these renewable energy sources are further developed and promoted worldwide. Rural areas used as the location of wind turbines often create conflict with the institutions managing such installations, due to the adverse effect on their operating objectives. The continuous ground vibrations often occupy a similar bandwidth to these installations, and interfere with sensitive measurements at key frequencies. As such, the magnitude and characteristics of the ground vibrations are a key component in determining the economics and expected power output of farms. Most seismological publications on the analysis of seismic signals from wind turbines to date assume naïve models of the earth and idealistic conditions that are not honoured in practice. Rural mountain locations with undulating topography, variable bedrock conditions and coupling lead to complex settings where the propagation of the seismic waves needs to be better understood. Another aspect of this problem is the nature of the wind turbine itself as a source of waves, whether as ground vibration or air borne infra-sound, and the relative influences of background noise versus wind turbine generated signal. There is still to date some uncertainty and discussion on whether the eigenfrequencies of the tower or blade speed are responsible for the signals we observe.
To address these challenges, and provide some clarity on the science, in this project we aim to model the tower and blade response using finite element modelling, analyse the coupling to realistic ground models, responses to wind speed and direction, and tie the results back to observations from seismic sensors in a real wind farm in the UK. The insights from this modelling will contribute to a better understanding of this source of vibration, the seismic waves that propagate, the extent to which waves decay with distance, and hence the critical radius of influence around such installations. We hope to generalise the results across a number of sites in Northern Europe. This work represents an intra-school collaboration between the Institute of Geoenergy Engineering and the Institute for Infrastructure and Environment. As such, the project will be jointly supervised by Professor Colin MacBeth and Professor Omar Laghrouche.
A successful candidate is expected to possess undergraduate and master’s degrees in either Applied Mathematics, Engineering, Physics and/or Geophysics. Understanding of the theory of seismic wave propagation, and use of finite difference and finite element modelling for solving coupled geomechanical and civil engineering applications would be an advantage.
To make an application, please visit the website.
The scholarship will cover tuition fees and provide an annual stipend of approximately £15,009 for the 36 month duration of the project and is available to applicants from the UK, EU and overseas.