The scope of this PhD thesis is the simulation of turbulence in time-dependent, separatedand suddenly-expanded channel flows. High-resolution and very high-order numericalmethods have been employed in the framework of Implicit Large Eddy Simulation (ILES)to elucidate open questions about the physics in flows with sudden expansion.It is well known that the planar sudden expansion (PSE), despite its simple and symmetricgeometry it produces a very complex behaviour and a distinctly asymmetric flowpattern ascribed mainly to the Coanda effect. Such flows are encountered in a wide rangeof practical engineering applications, such as combustion, hydraulic and fluidic devices,air ducts, and mixing equipments. It is of great importance, therefore, to understand themechanisms that dominate flows with separation and reattachment of the shear layers, aswell as flows with regions of strong reversed motion.This thesis has for the first time analysed in detail the turbulent kinetic energy budget(TKEB) for the PSE. This analysis has been extended to examine the influence of Machnumber on each individual component of the TKEB. The resulting data can be used asreference for further development of turbulence models capable of accurately resolvingthe flow behaviour in suddenly-expanded flows.Cont/d.
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