Search results for "IMPIANTI"
showing 10 items of 797 documents
On the numerical assessment of the thermo-mechanical performances of the DEMO Helium-Cooled Pebble Bed breeding blanket module
2014
Within the framework of the European DEMO Breeder Blanket Programme, a research campaign has been launched by University of Palermo, ENEA-Brasimone and Karlsruhe Institute of Technology to theoretically investigate the thermo-mechanical behavior of the Helium-Cooled Pebble Bed (HCPB) breeding blanket module of the DEMO1 blanket vertical segment, under normal operation and over-pressurization loading scenarios. The research campaign has been carried out following a theoretical-computational approach based on the finite element method (FEM) and adopting a qualified commercial FEM code. A realistic 3D FEM model of the HCPB blanket module central poloidal-radial region has been developed, inclu…
Steady, periodic, quasi-periodic and chaotic flow regimes in toroidal pipes
2012
Incompressible flow in a toroidal pipe was investigated by direct numerical simulation. The curvature a/c (radius of the cross section / radius of the torus) was 0.3 or 0.1 and the bulk Reynolds number ranged between 3500 and 14 700. The study revealed a rich scenario of transition to turbulence. For the higher curvature a/c = 0.3, a supercritical transition from stationary to periodic flow (Hopf bifurcation) was observed at Re=4600. The periodic flow was characterized by a travelling wave which, in the whole periodic Re range, took the form of a varicose modulation of the twin Dean vortex rings, included 8 wavelengths along the axis of the torus, and exhibited instantaneous anti-symmetry a…
Attività di interconfronto tra codici di trasporto atmosferico per la preparazione e la risposta alle emergenze nucleari
2019
In questo lavoro vengono presentati e confrontati i risultati ottenuti con tre differenti codici (FLEXPART, CALPUFF e ldX) per il trasporto atmosferico di inquinanti radioattivi. I codici vengono confrontati su una singola simulazione di un possibile rilascio incidentale alla stazione frontaliera di Gösgen (CH), in condizioni meteorologiche sfavorevoli per il territorio italiano. In this work we present and compare the results obtained iwth three different codes (FLEXPART, CALPUFF and ldX) for the atmospheric dispersion of radioactive pollutants. The codes are compared on a single simulation of a possible incident release in the Gösgen (CH) nuclear power plant with weather conditions that a…
DISPOSITIVO DATORE DI COPPIA PER PROVA DI INGRANAGGI MECCANICI, ROTISMI MECCANICI E SIMILI
2021
La presente invenzione riguarda un dispositivo che ha lo scopo di sottoporre a prova rotismi meccanici per la trasmissione di elevata potenza. L’impiego di tale dispositivo sostituisce, quindi, l’uso di freni di prova il cui impiego per elevate potenze risulta costoso e i cui ingombri sono rilevanti.
Predictive Study of Heat Transfer to an Incompressible Fluid Past a Downstream-Facing Step in Turbulent Flow
1988
On the influence of curvature and torsion on turbulence in helically coiled pipes
2014
Turbulent flow and heat transfer in helically coiled pipes at Retau=400 was investigated by DNS using finite volume grids with up to 2.36×10E7 nodes. Two curvatures (0.1 and 0.3) and two torsions (0 and 0.3) were considered. The flow was fully developed hydrodynamically and thermally. The central discretization scheme was adopted for diffusion and advection terms, and the second order backward Euler scheme for time advancement. The grid spacing in wall units was ~3 radially, 7.5 circumferentially and 20 axially. The time step was equal to one viscous wall unit and simulations were typically protracted for 8000 time steps, the last 4000 of which were used to compute statistics. The results s…