Coupled WRF-OpenFOAM study of wind flow over complex terrain

Abstract

This study addresses turbulence modelling issues related to the simulation of flow over complex terrain using a coupling between NWP (numerical weather prediction) code and a classical CFD (computational fluid dynamics) code. A new planetary boundary layer (PBL) parameterization scheme, which is specifically formulated for coupling purposes, is presented. The capability of the developed closure models to be applied to the whole atmospheric boundary layer, not only to the surface layer is assessed by performing idealized simulations and comparing the results with the Leipzig dataset. CFD simulations sustained with inflow conditions acquired from mesoscale simulations are performed with different turbulence closures for the Askervein Hill case and their performances are evaluated in comparison with wind speed and turbulence kinetic energy measurements. Finally, the proposed turbulence modelling methodology is applied to the Ria de Ferrol Case. The new PBL scheme is implemented and tested with the open source mesoscale code, Weather Research and Forecasting (WRF) model. Microscale simulations and the turbulence model implementation are performed with the open source computational fluid dynamics (CFD) toolbox, OpenFOAM v. 2.3.1.