The effect of grid resolution on large-Eddy-simulations for the a | 53552
Journal of Fundamentals of Renewable Energy and Applications

Journal of Fundamentals of Renewable Energy and Applications
Open Access

ISSN: 2090-4541

The effect of grid resolution on large-Eddy-simulations for the atmospheric boundary layer

World Congress and Exhibition on Wind & Renewable Energy

July 28-30, 2016 Berlin, Germany

Ioannis Bouras, Ava Shahrokhi, Mahyar Mahmoodilari, Derek Ingham, Lin Ma and Mohammed Pourkashanian

The University of Sheffield, UK

Scientific Tracks Abstracts: J Fundam Renewable Energy Appl

Abstract :

Air flow around a building has been simulated by employing LES and Smirnov��?s inflow generation technique. Accurate inflow data for LES are of paramount importance in order to obtain reliable results for the air velocity and turbulence levels. Otherwise, the flow shows a laminar behavior regardless of the Reynolds number and it requires several characteristic lengths to be recovered. Further, the initialization of the flow is among the top problems in wind engineering. In large Eddy simulations, velocity and turbulence profiles provide detailed information which is necessary for the wind resource assessment of wind turbines or wind farms that are positional at any height throughout the atmospheric boundary layer from any commercial CFD software. One of the biggest problems with LES is that the turbulence throughout the inlet of the computational domain must be fully prescribed. The present work shows the characteristics of the flow around a building by employing Smirnov��?s random flow generation technique for the inflow generation data. This study is a part of the European Project New innovative solutions, components and tools for the integration of wind energy in urban and peri-urban areas (acronym SWIP). The building is located in Saragossa in Spain, where a wind turbine will be installed. The energy spectrum is analyzed at different locations in the computational domain and the velocity fluctuations generated initially at the inlet and throughout the entire domain are proven to maintain the turbulence within the entire computational domain. This is also confirmed by the distribution of normal and shear Reynolds stresses throughout the domain. Finally, the present work illustrates the effect of the grid resolution on the results.

Biography :

Ioannis Bouras is a PhD student in the Energy Group in the Department of Mechanical Engineering of the University of Sheffield. He has completed his MSc in CFD course from the School of Engineering in Cranfield University in 2013. His main research area is on the atmospheric boundary layer investigating inflow generation techniques for LES/DNS and turbulence maintenance techniques throughout the atmospheric boundary layer.