Search results for "Structural engineering"
showing 10 items of 1998 documents
Assessment of DEMO WCLL breeding blanket primary heat transfer system isolation valve absorbed doses due to activated water
2020
Abstract Within the framework of the activities foreseen by the EUROfusion action on the cooling water activation assessment for a DEMO reactor equipped with a Water Cooled Lithium Lead Breeding Blanket (WCLL BB), the University of Palermo is involved in the investigation of the absorbed dose induced by the decay of nitrogen radioisotopes produced by water activation, in the main components (e.g. isolation valves) of both First Wall (FW) and Breeder Zone (BZ) cooling circuits. The aim of this work is to assess the spatial distribution of the absorbed dose in the DEMO Upper Pipe Chase (UPC), focusing the attention on the space neighbouring a typical isolation valve of the Primary Heat Transf…
A computational procedure for the investigation of whipping effect on ITER High Energy Piping and its application to the ITER divertor primary heat t…
2015
Abstract The Tokamak Cooling Water System of nuclear facility has the function to remove heat from plasma facing components maintaining coolant temperatures, pressures and flow rates as required and, depending on thermal-hydraulic requirements, its systems are defined as High Energy Piping (HEP) because they contain fluids, such as water or steam, at a pressure greater than or equal to 2.0 MPa and/or at a temperature greater than or equal to 100 °C, or even gas at pressure above the atmospheric one. The French standards contemplate the need to consider the whipping effect on HEP design. This effect happens when, after a double ended guillotine break, the reaction force could create a displa…
Assessment of tools for urban energy planning
2019
Abstract In recent years, studies and policies have encouraged the diffusion of distributed energy supply technologies and large integration of renewable sources. This increases the need for new professionals in energy planning. Several computational tools for energy planning have been developed as described in the technical literature. However, energy planners of urban/district areas engaged in the transition towards smart systems related to buildings energy services require well-documented tools to evaluate the combination of available energy sources by proper conversion technologies. With this, after a scientific review, we selected 17 tools targeted on an urban/districts scale that can …
Finite Element Studies On Friction Stir Welding Processes of Tailored Blanks
2008
Although friction stir welding (FSW) has been successfully used to join materials that are difficult-to-weld or unweldable by fusion welding methods, it is still in its early development stage and, therefore, its potential has not been fully exploited yet. FSW appears to be a very promising process for tailor-welded blanks to overcome the difficulties encountered in traditional fusion welding processes for obtaining a sound welding with good nugget integrity. In this paper the friction stir welding process for tailored blanks of aluminum alloy is investigated through a FEM developed by the authors. In particular FSW for sheets with different thicknesses is studied. For each setup a differen…
Platform switching on wide-diameter external hex implants: a finite element analysis.
2012
Objectives: The objective of this work was to use finite element analysis to compare the effect of forces coming to bear on abutments 4.1 or 5.0 mm in diameter connected to a 5.0 mm implant (i.e. with or without platform swit - ching). Study design: A 3D CAD model of a 5 x 11.5 mm external hex implant was developed, complete with a connection screw and either of two abutments, one 4.1 and the other 5 mm in diameter, to assess the influence of two loading conditions, i.e. 200 N loaded either axially or off center on the top of the abutment. Results and conclusions: In the symmetrically loaded models, greater stresses were transmitted to the bone in the area below the neck of the implant in t…
Extensible Wind Towers
2014
The diffusion of wind energy generators is restricted by their strong landscape impact. The PERIMA project is about the development of an extensible wind tower able to support a wind machine for several hundred kW at its optimal working height, up to more than 50 m. The wind tower has a telescopic structure, made by several tubes located inside each other with their axis in vertical direction. The lifting force is given by a jack-up system confined inside a shaft, drilled below the ground level. In the retracted tower configuration, at rest, tower tubes are hidden in the foundation of the telescopic structure, located below the ground surface, and the wind machine is the only emerging part …
Applying Artificial Intelligence Methods to Detect and Classify Fish Calls from the Northern Gulf of Mexico
2021
Passive acoustic monitoring is a method that is commonly used to collect long-term data on soniferous animal presence and abundance. However, these large datasets require substantial effort for manual analysis
Path integral solution for nonlinear systems under parametric Poissonian white noise input
2016
Abstract In this paper the problem of the response evaluation in terms of probability density function of nonlinear systems under parametric Poisson white noise is addressed. Specifically, extension of the Path Integral method to this kind of systems is introduced. Such systems exhibit a jump at each impulse occurrence, whose value is obtained in closed form considering two general classes of nonlinear multiplicative functions. Relying on the obtained closed form relation liking the impulses amplitude distribution and the corresponding jump response of the system, the Path Integral method is extended to deal with systems driven by parametric Poissonian white noise. Several numerical applica…
A model for evaluating the environmental and functional benefits of “innovative” roundabouts
2015
This study looks at the singling out of a multi-parameter criterion for choosing conventional or innovative roundabout layouts, by taking functional, environmental and economic aspects into consideration. The performances of three conventional roundabouts (with different lane number at entries and through the ring), turbo-roundabouts and roundabouts with right-turn bypass lane on all the arms (flower roundabouts) have been compared in terms of vehicle delays and pollutant (carbon dioxide, nitrogen oxides, particle pollution (PM10 and PM2.5)) emissions. By means of closed-form capacity models and with the help of COPERT IV© software, several traffic simulations have been carried out, referre…
Influence of coordinated traffic lights parameters on roadside pollutant concentrations
2009
Abstract The paper examines the effects of coordinated traffic lights on CO and C 6 H 6 roadside concentrations in an urban area of Palermo in Southern Italy. Traffic loop detectors and one pollution-monitoring are used to collect data for use in DRACULA traffic microsimulator software. CO and C 6 H 6 roadside concentrations associated with varying cycle and offset times of the coordinated traffic lights are estimated using a neural network. Two functions were set up describing the relations of pollutant concentrations in term of cycle and offset time.