|dc.contributor.author||Blair, Michael Barry||en
|dc.description.abstract||Improvements in wind flow modelling accuracy can impact positively on wind farm business
cases and therefore contribute towards meeting national and global energy decarbonisation
targets. ‘Atmospheric stability’ is a meteorological phenomenon which is often disregarded
in conventional wind flow modelling practice but which can have significant impact on wind
farm energy predictions. The concept relates to the reaction of the near-surface atmosphere
to diurnal and seasonal variation in the heating and cooling influences of the Earth’s surface.
This thesis details a demonstration of incorporating atmospheric stability effects into
Computational Fluid Dynamics (CFD) wind flow modelling methodology to improve wind farm
energy yield assessment and layout design.
Measurements of virtual potential temperature differential between 10m and 60 - 100m
above ground level (a proxy for atmospheric stability) were made at ten onshore and two
offshore sites. A comparison was then made between these measured data and commercially
available ‘Vortex’ Weather Research & Forecasting (WRF) mesoscale data and the latter was
shown to be a viable, cheaper and more readily accessible input data source.
A new technique for parametrising stability data was developed as part of a streamlined CFD-based
wind flow modelling approach. CFD simulations of key wind flow parameters (wind
shear, turbulence intensity and wind speed ratio) were made using both a ‘neutral’
assumption (a widely used industry-standard approach) and a more sophisticated ‘diabatic’
assumption, which incorporated site-specific inputs. These predictions were compared
against on-site measurements, demonstrating an overall improvement in modelling accuracy
when the diabatic assumption was implemented.
Energy yields for onshore wind farms with fixed layouts calculated using neutral and diabatic
flow modelling were shown to differ from one another by 1.4% on average (0.1 to 4.8%).
Further, onshore wind farm layouts optimised based on the diabatic flow modelling method
showed an average increase in predicted energy yield of 0.5% (0.1 to 1.1%) compared to those
optimised based on neutral flow modelling. For a mature energy technology such as onshore
wind, energy yield uplifts in this range can significantly impact project viability.||en
|dc.publisher||The University of Edinburgh||en
|dc.subject||wind farm design||en
|dc.subject||wind flow simulation||en
|dc.title||Consideration of atmospheric stability in wind energy modelling||en
|dc.type||Thesis or Dissertation||en
|dc.type.qualificationname||PhD Doctor of Philosophy||en