Application of WRF/Fluent coupling to the analysis of atmospheric turbulence around the Orchid Island

Abstract

There is an increasing interest predominantly away from coast Thus it is necessary to accurately model and simulate wind flow over complex terrain for forecasting and optimizing wind energy production Simulating the wind flows using the real wind conditions over the wind farm is highly recommended to investigate on the atmospheric boundary layer The real ABL contains several characteristics that have not been considered in this research such as flow stratification based on varying weather conditions The effects of buoyancy which is neglected in this research can be included in any future work which makes the modeling flows more challenging as the effects on the atmosphere changes rapidly The aim of this research is to simulate and analyze the wind flow characteristics around a complex terrain the Orchid Island in Taiwan using Reynolds Averaged Navier-Stokes equation (RANS) which are prominent when considering the wind energy air and maritime transportation The mesh independency has been evaluated first then a uniform constant boundary conditions has been applied to determine the suitable 2-equation turbulence model between (k-ω SST k-ε EWT k-ω) After selecting k-ω SST the 2-equation turbulence model has used to run a simulation over the four directions of the domain WRF has been coupled with FLUENT using a surface B spline interpolation and using the 2-equation turbulence model (k-ω SST) to evaluate the turbulent flows over complex terrains using under real atmospheric conditions From the results the impact of the terrain and canopy terrain on the flow near the import could be observed The results also showed that the current WRF/Fluent coupling has the potential to predict wind speed acceptably well when the inlet flow direction is less complex and under low wind speed Additionally more than 50 % reduction in error with WRF/Fluent coupling compared to WRF alone is achieved and a maximum error of about 20% between observed data and WRF/Fluent coupling using B spline surface interpolation is achieved Finally the development of the turbulence generated by wind coming from the most complex domain can create challenges for a pilot trying to land an aircraft at the airport

Date of Award	2019
Original language	English
Supervisor	Jiun-Jih Miau (Supervisor)