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Zheng-Tong Xie (AFM group, FEE). An efficient inflow generation for large-eddy simulation of wind/tide turbine flows. Questions and approaches. Why turbulence? Why bother to use LES and to develop inflow generation method? (LES for large separation, peak loading, providing parameterisation)
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Zheng-Tong Xie (AFM group, FEE) An efficient inflow generation for large-eddy simulation of wind/tide turbine flows
Questions and approaches Why turbulence? Why bother to use LES and to develop inflow generation method? (LES for large separation, peak loading, providing parameterisation) Current inflow approaches - inefficient, divergence-free not considered (e.g. inlet velocities does not satisfy continuity eq). Why divergence-free required? (when peak loading, acoustic issues are of interest). We developed a simple and efficient inflow generation –500 times faster than the old ones; artificial p flucts. significantly reduced. Applications: wind turbine flows, ventilation in large buildings, heat transfer at building surfaces.
LES of flows around a static wind-turbine blade Laminar inlet Turbulent inlet, TI=8% Spanwise-component of vorticity at mid-span of a NACA0006 blade at α =7˚, Re =50,000 (Kim, Xie, Castro 2011)
Pressure fluctuations at x/d=30 Divergence free inflow conditions for a plane channel flow О~103 reduced! Div. non-free Div. free Ref data (Kim, Xie, Castro 2012)