Search results for "Thermal"
showing 10 items of 3576 documents
Magma extrusion during the Ubinas 2013-2014 eruptive crisis based on satellite thermal imaging (MIROVA) and ground-based monitoring
2015
After 3 years of mild gases emissions, the Ubinas volcano entered in a new eruptive phase on September 2nd, 2013. The MIROVA system (a space-based volcanic hot-spot detection system), allowed us to detect in near real time the thermal emissions associated with the eruption and provided early evidence of magma extrusion within the deep summit crater. By combining IR data with plume height, sulfur emissions, hot spring temperatures and seismic activity, we interpret the thermal output detected over Ubinas in terms of extrusion rates associated to the eruption. We suggest that the 2013–2014 eruptive crisis can be subdivided into three main phases: (i) shallow magma intrusion inside the edifice…
On the effects of the Double-Walled Tubes lay-out on the DEMO WCLL breeding blanket module thermal behavior
2019
Abstract The EU-DEMO Water-Cooled Lithium Lead Breeding Blanket (WCLL BB) concept foresees liquid Pb-15.7Li eutectic alloy as breeder and neutron multiplier, whereas pressurized subcooled water as coolant, with operative conditions typical of the PWR fission reactors (temperature in the range of 295–328 °C and pressure of 15.5 MPa). The cooling down of the BB is guaranteed by means of two separated cooling circuits: the one consisted in square channels housed within the complex of Side Walls and First Wall, and the one composed of a set of Double-Walled Tubes (DWTs) submerged in the Breeding Zone (BZ) and deputed to remove heat power therein generated. A parametric thermal study has been ca…
On the effectiveness of Finite Element simulation of orthogonal cutting with particular reference to temperature prediction
2007
Abstract Finite Element simulation of orthogonal cutting is nowadays assuming a large relevance; in fact a very large number of papers may be found out in technical literature on this topic. In recent years, numerical simulation was performed to investigate various phenomena such as chip segmentation, force prediction and tool wear. On the other hand, some drawbacks have to be highlighted; due to the geometrical and computational complexity of the updated-Lagrangian formulation mostly used in FE codes, a cutting time of only a few milliseconds can be effectively simulated. Therefore, steady-state thermal conditions are not reached and the simulation of the thermal phenomenon may be ineffect…
Parametric study of the influence of double-walled tubes layout on the DEMO WCLL breeding blanket thermal performances
2020
Abstract Within the framework of the EUROfusion activities regarding the EU-DEMO Breeding Blanket (BB) concept, the University of Palermo is long-time involved, in close cooperation with ENEA, in the design of the Water Cooled Lithium Lead (WCLL) BB, that is one of the two concepts under consideration for the DEMO reactor. It is mainly characterized by a liquid lithium-lead eutectic alloy acting as breeder and neutron multiplier, as well as by subcooled pressurized water flowing as coolant under PWR-like conditions (pressure of 15.5 MPa and inlet/outlet temperatures of 295 °C/328 °C). A research campaign has been recently carried out to study the potential influence of the Breeding Zone coo…
Methods for Determining the Thermal Transfer in Phase-Changing Materials (PCMs).
2020
A very important issue that needs to be solved as simply and correctly as possible is how to establish the thermal performance of phase-changing materials (PCM). The undertaken researches have analyzed the values of the thermal performances of the PCM taking into account the method of finite elements and the experimental research, respectively, based on a modern measurement system that was designed and implemented. Butyl stearate which has been encapsulated through complex coacervation in polymethyl methacrylate has been used as a PCM. Samples were made containing 10%, 20%, 30% and 40% PCM, respectively, within their structure. The research has established that at both the hot plate and the…
Mapping snow density through thermal inertia observations
2023
Snow, as a fundamental reservoir of freshwater, is a crucial natural resource. Specifically, knowledge of snow density spatial and temporal variability could improve modelling of snow water equivalent, which is relevant for managing freshwater resources in context of ongoing climate change. The possibility of estimating snow density from remote sensing has great potential, considering the availability of satellite data and their ability to generate efficient monitoring systems from space. In this study, we present an innovative method that combines meteorological parameters, satellite data and field snow measurements to estimate thermal inertia of snow and snow density at a catchment scale.…
Compact 20-pass thin-disk amplifier insensitive to thermal lensing
2019
We present a multi-pass amplifier which passively compensates for distortions of the spherical phase front occurring in the active medium. The design is based on the Fourier transform propagation which makes the output beam parameters insensitive to variation of thermal lens effects in the active medium. The realized system allows for 20 reflections on the active medium and delivers a small signal gain of 30 with M$^2$ = 1.16. Its novel geometry combining Fourier transform propagations with 4f-imaging stages as well as a compact array of adjustable mirrors allows for a layout with a footprint of 400 mm x 1000 mm.
Effect of nanostructuration on the spin crossover transition in crystalline ultrathin films† †Electronic supplementary information (ESI) available: M…
2019
Film thickness and microstructure critically affect the spin crossover transition of a 2D coordination polymer.
Synthesis of self-assembled mesoporous 3D In2O3 hierarchical micro flowers composed of nanosheets and their electrochemical properties
2018
This report describes the methodology for the fabrication of mesoporous In2O3 microflowers by hydrothermal and calcination procedures in which In(OH)3/In2S3 acts as an intermediate. Both In2O3 and its precursor were analyzed with scanning electron microscopy, energy dispersive X-ray spectrophotometry, transmission electron microscopy and powder X-ray diffraction. BET surface area, pore size and pore volume analyses were also carried out. Electron microscopy images clearly evidence the self-assembly of 2D nanosheets into the micro flower structure. The mechanism of self-assembly and calcination is reported. Electrochemical properties of the synthesized In2O3 micro flowers were studied.
Monitoring the Growth of a Microbubble Generated Photothermally onto an Optical Fiber by Means Fabry-Perot Interferometry.
2021
In the present paper, we show the experimental measurement of the growth of a microbubble created on the tip of a single mode optical fiber, in which zinc nanoparticles were photodeposited on its core by using a single laser source to carry out both the generation of the microbubble by photothermal effect and the monitoring of the microbubble diameter. The photodeposition technique, as well as the formation of the microbubble, was carried out by using a single-mode pigtailed laser diode with emission at a wavelength of 658 nm. The microbubble’s growth was analyzed in the time domain by the analysis of the Fabry–Perot cavity, whose diameter was calculated with the number of interference frin…