Validation of the Model PALM-4U against Observation Campaign in Prague-Dejvice

Abstract

Investigation of the urban climate has become very important during recent years and aims to help urban city authorities to plan efficient and economically feasible mitigation strategies to counteract the adverse effects of the urban heat island phenomenon (UHI). Different modelling approaches have been used for this purpose and models based on computational fluid dynamic (CFD) techniques represent the most advanced method. Two main approaches are used in this category. The Reynolds-averaged Navier–Stokes equations (RANS) method calculates only the mean flow while the turbulence is fully parameterized, while the large-eddy simulation (LES) approach models explicitly the resolved turbulent flow and parameterizes only the subgridscale unresolved turbulence. The LES approach is more computationally demanding, but many studies have shown that it significantly outperforms RANS for simulations in complex urban environments.