Search results for "CPB"

Short-term and long-term results of cardiac surgery in elderly and very elderly patients

2011

Objective: Cardiac operations in elderly patients are increasingly frequent and imply major clinical, ethical, and economic issues. Operative and 5-year results of cardiac operations in patients aged 79 years or more are known in limited series, and a debate is ongoing on the appropriateness of selection of patients for surgery. Methods: We retrospectively reviewed our experience in 6802 patients aged 79 years or more who had received a cardiac operation. Surgical candidates were selected according to functional status, crude operative risk, and social context and were managed according to a multimodality protocol. Results: Mean age was 82 years and surgery was nonelective in 1613 cases (23…

Experimental tests and thermo-mechanical analyses on the HEXCALIBER mock-up

2008

Abstract Within the framework of the R&D activities promoted by European Fusion Development Agreement on the helium-cooled pebble bed test blanket module to be irradiated in ITER, ENEA Brasimone and the Department of Nuclear Engineering of the University of Palermo performed intense research activities on the modelling of the thermo-mechanical behaviour of both beryllium and lithiated ceramics pebble beds, which are envisaged to be used, respectively, as neutron multiplier and tritium breeder. In particular, at the DIN a thermo mechanical constitutive model was developed for both lithiated ceramics and beryllium pebble beds and it was successfully implemented on a commercial finite element …

On the theoretical–numerical study of the HEXCALIBER mock-up thermo-mechanical behaviour

2010

Abstract Within the framework of the R&D activities promoted by European Fusion Development Agreement on the Helium-Cooled Pebble Bed Test Blanket Module to be irradiated in ITER, ENEA Brasimone and the Department of Nuclear Engineering of the University of Palermo (DIN) performed intense research activities on the modelling of the thermo-mechanical behaviour of both beryllium and lithiated ceramics pebble beds, that are envisaged to be used, respectively, as neutron multiplier and tritium breeder. In particular, the DIN developed a thermo-mechanical constitutive model for these pebble beds to be validated against the HEXCALIBER mock-up test campaign, carried out at the ENEA HE-FUS3 facilit…

A multi-physics integrated approach to breeding blanket modelling and design

2019

Abstract Often, for the design of a component, several kinds of analyses are needed. Even more frequently, the different fields of study, to be taken into account for the design verification, have to be examined minutely until the final results are satisfying. Furthermore, when geometry modifications are required, for instance to fulfill the component functions, the analyses cycle has to be restarted and an iterative process has to be carried out. This procedure may be time-consuming and herald of errors, in particular if it is demanded to the human activity. Therefore, it is more convenient for the scientific community to adopt a numerical tool that can combine various computational codes.…

Thermal-hydraulic and thermal-structural analyses report of DEMO Helium-Cooled Pebble Bed blanket

2012

Thermomechanical analyses of the DEMO-HCPB TBM medium scale mock-up to be tested in the HE-FUS3 facility

2000

Thermal tests of ceramic breeder pebble beds for the Helium Cooled (HCPB) DEMO blanket

2002

Automated parametric neutronics analysis of the Helium Cooled Pebble Bed breeder blanket with Be 12 Ti

2017

The Helium Cooled Pebble Bed (HCPB) breeder blanket is being developed as part of the European Fusion Programme. Part of the programme is to investigate blanket designs relevant for future demonstration fusion power plants. This paper presents neutronics analyses of the HCPB with an alternative neutron multiplier, Be12Ti which is incorporated into the design, replacing the current Be multiplier. A parameter study was performed for a range of geometries to identify the optimal heights of the lithium ceramic and neutron multiplier pebble beds. Automated creation of CAD models followed by conversion to constructive solid geometry (CSG) and unstructured mesh (UM) geometry allows the models to b…

Overview of the HCPB Research Activities in EUROfusion

2018

In the framework of the EUROfusion’s Power Plant Physics and Technology, the working package breeding blanket (BB) aims at investigating four different BB concepts for an EU demonstration fusion reactor (DEMO). One of these concepts is the helium-cooled pebble bed (HCPB) BB, which is based on the use of pebble beds of lithiated ternary compounds and Be or beryllides as tritium breeder and multiplier materials, respectively, EUROFER97 as structural steel and He as coolant. This paper aims at giving an overview of the EU HCPB BB Research and Development (R&D) being developed at KIT, in collaboration with Wigner-RCP, BUTE-INT, and CIEMAT. The paper gives an outline of the HCPB BB design evolut…

An enhanced, near-term HCPB design as driver blanket for the EU DEMO

2019

The Helium Cooled Pebble Bed (HCPB) breeding blanket is a candidate as driver blanket for the EU DEMO. The reference design of the HCPB is based on a cooling plate “sandwich” arrangement built in Multi-Module Segments. This architecture significantly improved the tritium breeding performance (TBR = 1.15) and the plant circulating power (≈130 MW) compared to the former ITER-like “beer-box”-like design (TBR<1.10, plant circulating power>200 MW). However, several issues remain with this design, in which (1) the still large power required per He circulator (beyond the state-of-the-art for these components) and (2) the large tritium inventory foreseen in Be have been identified as the most…