Il messagio alla redazione del sito RSE è stato inviato
Il messaggio al referente RSE è stato inviato
i dati sono stati inseriti correttamente. Per attivare la registrazione, seleziona il link nel testo del messaggio appena inviato all’indirizzo email specificato.
This paper presents a general semi-analytic approach for modelling solid boundaries in the SPH method: boundaries are here considered as a material continuum with a suitable distribution of velocity and pressure; their contributions to each term of the SPH mass and momentum equations can be expressed in terms of a suitable integral extended to the part of the sphere of influence of the particle delimited by the boundary surface. Analytical details with reference to a slightly compressible viscous Newtonian fluid in three dimensions are given. The validity of the method is checked by comparing the obtained numerical results with available experimental data in a benchmark flow case.
This work shows an application of the Smoothed Particle Hydrodynamics (SPH) for the numerical modeling of engineering problems involving rapid evolution over time, high strain and gradients, heterogeneity, deformable contours and the presence of mobile material interfaces. Following a Lagrangian approach the continuum is discretized by means of a finite number of material particles carrying physical properties and moving according to Newton’s equations of the classical physics. Spatial derivatives of a variable at a point are approximated by using the information on the neighboring particles based on the kernel approximation. This paper recalls the basics of the method along with some numerical aspects concerning boundaries treatment, time integration scheme etc.; furthermore some details are provided about the recent improvements carried out for SPH simulations of: a) non-cohesive sediment flushing by rapid water discharge in an hydropower reservoir, b) underwater explosion for bottom sediment resuspension in an artificial reservoir. Numerical examples are illustrated and discussed concerning 2D and 3D test cases carried out with the aim of investigating the basic features of both sediment dynamics and gas explosion: obtained results shows that the SPH method can be applied to model the relevant engineering aspects of the considered problems and can be a helpful tool for future design applications in the field of hydropower reservoir management.
31 Dicembre 2010
Studi su potenziali sviluppi delle energie rinnovabili (P04PROD)