Search results for "CFD analysi"

Integrated multi-physics design tool for fusion breeding blanket systems - development and validation

2020

Il Breeding Blanket (BB) del reattore DEMO rappresenta un sistema complesso in un ambiente pericoloso. Infatti, esso deve soddisfare diversi requisiti e vincoli ingegneristici sia di tipo nucleare, termo-strutturale che di sicurezza. Per questi motivi, è necessaria una progettazione omnicomprensiva che preveda l'applicazione di strumenti avanzati di simulazione basati su approcci multi-fisici. Questi strumenti devono eseguire simultaneamente diversi tipi di analisi. Tre di esse possono essere considerate prioritarie e propedeutiche per lo studio di tutti gli altri fenomeni riguardanti il BB, vale a dire l´analisi nucleare, termo-fluidodinamica e strutturale. In questa tesi, è proposto un in…

THERMOFLUID-DYNAMICS OF DEMO DIVERTOR CASSETTE

2023

The divertor is a critical in-vessel component of nuclear fusion reactors, being responsible for the fulfilment of certain fundamental functions for the machine: it must be able to handle the power deposited by charged particle and neutron irradiation, ensure the presence of channels through which the fusion ashes can be removed from the Vacuum Vessel (VV), provide plasma-compatible surfaces, and shield the VV and magnets from nuclear loads. The heat load that can be tolerated by the divertor under normal and off-normal operating conditions is a pivotal parameter when dimensioning a fusion power plant since exceptionally high heat fluxes can be observed in some regions of the divertor, in t…

Caractérisation et prédiction du rendement de projection lors du procédé de projection à froid – cas de la métallisation des polymères

2020

This thesis work deals with the cold spray metallization of polymer substrates by aiming at an optimal deposition efficiency using experimental analysis combined with numerical simulation. Experimental observations of the powder jet using an ombroscopic analysis have revealed a generic behavior consisting of a uniform confined zone at the immediate exit of the nozzle followed by a dispersed zone. The supersonic flow at the nozzle exit being essentially axial, the powders are entrained to form a uniform jet. Beyond a certain distance, a dispersion appears. This distance is very important because it characterizes the behavior of the powders. It can alter the conditions for the elaboration of …

Thermofluid-dynamic assessment of the EU-DEMO divertor single-circuit cooling option

2023

Until 2019, the thermo-hydraulic development of the EU-DEMO divertor was based on the “double-circuit” concept, in which two independent cooling circuits served by two different Primary Heat Transfer Systems were used to cool the Plasma-Facing Components (PFC) and the Cassette Body (CB). During the Divertor Final Design Review Meeting, held in May 2020, the possibility to adopt a single cooling circuit to serve both components was suggested. This new cooling circuit was originally conceived with the aim of simplifying remote maintenance, with potential benefits for some aspects of safety and balance of plant design and integration. During the years from 2020 to 2022, in the fram…

Slotted Blades Savonius Wind Turbine Analysis by CFD

2013

In this paper a new bucket configuration for a Savonius wind generator is proposed. Numerical analyses are performed to estimate the performances of the proposed configuration by means of the commercial code COMSOL Multiphysics® with respect to Savonius wind turbine with overlap only. Parametric analyses are performed, for a fixed overlap ratio, by varying the slot position; the results show that for slot positioned near the blade root, the Savonius rotor improves performances at low tip speed ratio, evidencing a better starting torque. This circumstance is confirmed by static analyses performed on the slotted blades in order to investigate the starting characteristic of the proposed Savoni…

Coupled Hydraulic and Electronic Regulation for Banki Turbines

2016

Abstract The potential benefit of coupling hydraulic and electronic regulation to maximize the energy production of a Bank turbine in hydraulic plants is analyzed and computed with reference to a specific case. Design criteria of the Banki turbine inside hydraulic plants are first summarized, along with the use of hydraulic regulation in the case of constant water head and variable discharge at the end of aqueducts feeding water distribution systems. Optimal turbine impeller rotational speed is derived and traditional, as well as innovative systems for electricity production according to controlled rotational speed of the generator are presented. The study case at the purification plant nam…

Analysis of steady state thermal-hydraulic behaviour of the DEMO Divertor cassette body cooling circuit

2017

Abstract Within the framework of the Work Package DIV 1 – “Divertor Cassette Design and Integration” of the EUROfusion action, a research campaign has been jointly carried out by ENEA and University of Palermo to investigate the thermal-hydraulic performances of the DEMO divertor cassette cooling system. A comparative evaluation study has been performed considering the two different options under consideration for the divertor cassette body coolant, namely subcooled pressurized water and helium. The research activity has been carried out following a theoretical-computational approach based on the finite volume method and adopting a qualified Computational Fluid-Dynamic (CFD) code. CFD analy…

Computerized dynamic fluid simulation (CFD) for measuring the influence of the cab deflector on the aerodynamics of trucks

2021

This paper refers to how the cab deflector of trucks can influence the aerodynamic coefficient. The first part of the paper includes some generalities taken from previous studies, regarding the types of solutions to improve aerodynamics for trucks. The second part of the paper is a more practical one and has two main chapters: modeling and simulation of modeled parts. In this sense, a truck and 3 cabin deflectors were schematically modeled in Catia v5. After assembly in the Catia v5 program, the impact of the cabin deflector was analyzed. Thus, a computerized dynamic fluid simulation (CFD) was performed using the specific module in Ansys. The simulation included the CFD analysis of the four…

Liberty winter gardens in Palermo: contamination from solar design

2020

At the end of the 19th century, the city of Palermo boasted a tradition of steel elements that could include the most beautiful railings and light steel structures of the time. The paper shows how the technological, formal and spatial aspects of the metallic construction was derived by the application of Central Europe areas examples to the local reality, providing notions on designs, experimentations and originalities. Canopies, verandas, winter gardens and orangeries are architectural elements in iron and glass that represent an added value for the building, they improve the life quality of the people who live there. In particular, in the Liberty architecture these elements took shape thr…

Numerical assessment of the thermal-hydraulic performances of the ITER Blanket cooling system

This thesis has covered the main research activities carried out during the candidate Ph.D. course of the XXXI Cycle on “Energia e Tecnologie dell’Informazione - curriculum Fisica Tecnica e Ingegneria Nucleare” (Energy and Information Technologies - Applied Physics and Nuclear Engineering curriculum), held at the University of Palermo, in the time frame that goes from the end of 2015 to the end of 2018. In particular, it focusses on the activities carried out at the DEIM in cooperation with the ITER Organisation on the “Hydraulic Analysis of Blanket Cooling System” and it has aimed to investigate the thermal-hydraulic behaviour of the ITER blanket cooling system under nominal steady-state c…