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This paper presents a selection of CFD investigations on ship and propeller hydrodynamics performed in the frame of an extensive benchmarking activity, presently undertaken in the frame of the OpenSHIP Project - Highly reliable CFD simulations for the prediction of the hydrodynamic performance of the hull-propeller system with OpenSource software - co-financed by the ERDF - European Regional Development Fund - Friuli Venezia Giulia Region Operational Programme 2007 - 2013. Spilling breaking and non-breaking waves induced by a foil at constant speeds underneath the free surface are presented first. The wake at the propeller disk of a double model hull – MOERI KCS - is then analyzed, and finally the numerical predictions of the propulsive characteristics of two different model scale propellers are presented. All the simulations are carried out using the OpenFOAM-2.1.0 CFD package, and the numerical results are compared with available experimental data.

Il lavoro presenta lo studio di fattibilità tecnica di impianto di teleriscaldamento per una Comunità Montana usando biomassa forestale. Sono presentati i risultati del dimensionamento del sistema di generazione del calore e del sistema di vettoriamento e distribuzione. La procedura utilizzata può essere estesa presso altre realtà territoriali con caratteristiche simili.

In un precedente lavoro [120], è stata presentata la fattibilità tecnica di un impianto di teleriscaldamento per una Comunità Montana usando biomassa forestale. In questo lavoro sono proposte la fattibilità economica e l’impatto ambientale per lo stesso impianto. Successivamente è stato sviluppato lo studio di impatto ambientale tenendo conto dei quadri riferimento di programmatico, progettuale e ambientale. In particolare, è stato analizzato qualificato e quantificato l’inquinamento prodotto dall’impianto comparandolo con quello prodotto dagli impianti termici civili che sono attualmente in esercizio nell’area considerata.

Direct Numerical Simulation (DNS) of turbulent flow and heat transfer requires that most of the energy-containing length and time scales must be accurately captured. The spatial resolution can be augmented in two complementary ways, i.e. either the grid spacing has to be reduced, by refining the computational mesh, or a more accurate spatial approximation should be used. In this work we present our approach for the development of a fourth-order, compact finite volume scheme for the DNS of incompressible turbulent flow and heat transfer. The numerical method is fourth order accurate, but it is shown that a further increase of accuracy does not represent a difficult task, and can be accomplished in a modular way. A staggered grid arrangement is employed, which presents well-known advantages concerning properties conservation and absence of unphysical pressure oscillations, of paramount importance in DNS. In this paper, after a concise description of the method, we present several test cases, which illustrate the main characteristics and capabilities of the proposed methodology.