Search results for "Nuclear engineering"

Internal geometry and coolant choices for solid high power neutron spallation targets

2014

Abstract The next generation of neutron spallation sources envisages high power proton beam interaction with a heavy metal target. Solid targets have potentially higher spallation efficiency due to the possibility to use metals with higher density than used in liquid metal targets, but to realize this potential the solid fraction must be high enough. As the power released in the form of heat can reach several MW in the target volume of typically 10 l, target cooling can be a serious challenge. Heat evacuation efficiency for different solid fraction geometries at high power is analyzed for different coolant options (helium, water and gallium) using empirical correlations for friction factors…

A study of the potential influence of frame coolant on HCLL-TBM nuclear response

2007

Abstract Within the European Fusion Technology Programme, the Helium-Cooled Lithium Lead (HCLL) breeding blanket concept is one of the two EU lines to be developed for a long term fusion reactor, in particular with the aim of manufacturing a test blanket module (TBM) to be implemented in ITER. The HCLL-TBM is foreseen to be located in an ITER equatorial port, being housed inside a steel-supporting frame, actively cooled by pressurized water. This supporting frame has been designed to house two different TBMs providing two cavities separated by a dividing plate 20 cm thick. As the nuclear response of HCLL-TBM could vary with the supporting frame configuration and composition, a parametric st…

Development of integrated superconducting quadrupole doublet modules for operation in the SIS100 accelerator

2015

The FAIR project (Facility for Antiproton and Ion Research) evolves and builds an international accelerator- and experimental facility for basic research activities in various fields of modern physics. Within the course of this project, integrated quadrupole doublet modules are in development. The quadrupole doublet modules provide a pair of superconducting main quadrupoles (focusing and defocusing), corrector magnets, cryogenic collimators and beam position monitors as integrated sets of ion-optical elements. Furthermore LHe cooled beam pipes and vacuum cold-warm transitions are used as ultra-high vacuum components for beam transportation. Superconducting bus bars are used for 13 kA curren…

A low phase noise microwave source for high‐performance CPT Rb atomic clock

2021

Abstract Phase noise of the frequency synthesizer is one of the main limitations to the short‐term stability of microwave atomic clocks. Here, a low‐noise, simple‐architecture microwave frequency synthesizer for a coherent population trapping (CPT) clock is demonstrated. The synthesizer is mainly composed of a 100 MHz oven‐controlled crystal oscillator (OCXO), a microwave comb generator, and a direct digital synthesizer (DDS). The absolute phase noises of 3.417 GHz signal are measured to be −55 dBc/Hz, −81 dBc/Hz, −111 dBc/Hz and −134 dBc/Hz, respectively, for 1 Hz, 10 Hz, 100 Hz and 1 kHz offset frequencies, which shows only 1 dB deterioration at the second harmonic of the modulation frequ…

Nuclear energy and radiochemistry

2007

Assessment of the Possible Lay-Out Influence on the HCLL-TBM Nuclear Response

2009

The Department of Nuclear Engineering of the University of Palermo (DIN) was involved, since several years, in the study of the nuclear response of the helium-cooled lithium lead (HCLL) test blanket module (TBM) which will be tested in ITER. In this framework a research campaign was performed, at the DIN, to asses the nuclear response of the TBM in a toroidal lay-out, with the specific aim to investigate the possible lay-out influence on the module nuclear behaviour by comparing the results obtained with those presented in a similar previous work focussed on the most recent design of the poloidal HCLL-TBM. A computational approach based on the Monte Carlo method was followed and a realistic…

Construction, Commissioning and First Results of a Highly Granular Hadron Calorimeter with SiPM-on-Tile Read-out

2018

The CALICE collaboration is developing a highly granular Analogue Hadron sampling CALorimeter (AHCAL) for a future electron-positron collider. Very small detection units are required for the AHCAL due to an optimized design for the Particle Flow Algorithm. This is realized with scintillator tiles each wrapped in reflector foil and individually read out by a silicon photomultiplier (SiPM). These scintillator tiles and SiPMs are assembled on readout boards (HCAL Base Unit, HBU) which are integrated later on in the AHCAL detector stack. With this design a higher energy resolution is achievable, but also a large quantity of components (around 8,000,000 scintillator tiles and SiPMs) are needed t…

On the use of stacks of fission-like targets for neutron capture experiments

2019

The measurement of neutron induced reactions on unstable isotopes is of interest in many fields, from nuclear energy to astrophysics or applications; in particular transuranic isotopes are essential for the development of innovative nuclear reactors and for the management of the radioactive waste. In such measurements, the quality of the associated radioactive target is crucial for the success of the experiment, but in many cases the geometry, amount of mass and encapsulation of the target are not optimal, leading to limited results. In this work we propose to produce high quality radioactive targets for capture as a stack of thin targets using the techniques usually employed for fission me…

Detection of a structural impact in liquid metal flow during test runs of the EURISOL target mock-up

2009

Abstract The many possible applications of Liquid Metal (LM) technology promise improved thermal efficiency, which can provide much-needed impetus to finding solutions for the growing world energy needs, as well as increasing the accuracy and power of certain delicate scientific apparatus used in the materials and biological sciences. The development of appropriate safeguards and instrumentation is critical to continued progress in this area of technology. During the hydraulic test of the EURISOL liquid metal target, a component failure was registered by the instrumentation; its detection in the presence of liquid metal flow was critical to ensuring the safety of both the personnel and the …

Structural-hydraulic test of the liquid metal EURISOL target mock-up

2009

Abstract Structural-hydraulic tests of the European Isotope Separation On-Line (EURISOL) neutron converter target mock-up, named MErcury Target EXperiment 1 (METEX 1), have been conducted by Paul Scherrer Institut (PSI, Switzerland) in cooperation with Institute of Physics of the University of Latvia (IPUL, Latvia). PSI proceeded with extensive thermal-hydraulic and structural computational studies, followed by the target mock-up tests carried out on the mercury loop at IPUL. One of the main goals of the METEX 1 test is to investigate the hydraulic and structural behaviour of the EURISOL target mock-up for various inlet flow conditions (i.e. mass flow rates) and, in particular, for nominal …