qualitative thermal characterization and cooling of lithium batteries for electric vehicles

The paper deals with the cooling of batteries. The first step was the thermal characterization of a single cell of the module, which consists in the detection of the thermal field by means of thermographic tests during electric charging and discharging. The purpose was to identify possible critical hot points and to evaluate the cooling demand during the normal operation of an electric car. After that, a study on the optimal configuration to obtain the flattening of the temperature profile and to avoid hot points was executed. An experimental plant for cooling capacity evaluation of the batteries, using air as cooling fluid, was realized in our laboratory in ENEA Casaccia. The plant is designed to allow testing at different flow rate and temperatures of the cooling air, useful for the assessment of operative thermal limits in different working conditions. Another experimental facility was built to evaluate the thermal behaviour changes with water as cooling fluid. Experimental tests were carried out on the LiFePO4 batteries, under different electric working conditions using the two loops. In the future, different type of batteries will be tested and the influence of various parameters on the heat transfer will be assessed for possible optimal operative solutions

Self-Consistent 3D Modeling of Electron Cloud Dynamics and Beam Response

We present recent advances in the modeling of beam electron-cloud dynamics, including surface effects such as secondary electron emission, gas desorption, etc, and volumetric effects such as ionization of residual gas and charge-exchange reactions. Simulations for the HCX facility with the code WARP/POSINST will be described and their validity demonstrated by benchmarks against measurements. The code models a wide range of physical processes and uses a number of novel techniques, including a large-timestep electron mover that smoothly interpolates between direct orbit calculation and guiding-center drift equations, and a new computational technique, based on a Lorentz transformation to a moving frame, that allows the cost of a fully 3D simulation to be reduced to that of a quasi-static approximation

Status of Muon Collider Research and Development and Future Plans

The status of the research on muon colliders is discussed and plans are outlined for future theoretical and experimental studies. Besides continued work on the parameters of a 3-4 and 0.5 TeV center-of-mass (CoM) energy collider, many studies are now concentrating on a machine near 0.1 TeV (CoM) that could be a factory for the s-channel production of Higgs particles. We discuss the research on the various components in such muon colliders, starting from the proton accelerator needed to generate pions from a heavy-Z target and proceeding through the phase rotation and decay ($\pi \to \mu \nu_{\mu}$) channel, muon cooling, acceleration, storage in a collider ring and the collider detector. We also present theoretical and experimental R & D plans for the next several years that should lead to a better understanding of the design and feasibility issues for all of the components. This report is an update of the progress on the R & D since the Feasibility Study of Muon Colliders presented at the Snowmass'96 Workshop [R. B. Palmer, A. Sessler and A. Tollestrup, Proceedings of the 1996 DPF/DPB Summer Study on High-Energy Physics (Stanford Linear Accelerator Center, Menlo Park, CA, 1997)].Comment: 95 pages, 75 figures. Submitted to Physical Review Special Topics, Accelerators and Beam

Should I give kids money? The role of pocket money on at-risk behaviors in Italian adolescents

Background. Discussion on the impact of pocket money on positive behaviors is still debated. Objective. To investigate the effect of diverse money allowance schemes on risky behaviors (smoking, alcohol, binge drinking, drug use, gambling) during adolescence. Method. 989 students aged 15 from Lombardy (Italy) reported information on money availability in the 2018 wave of the Health Behaviour in School-aged Children study. To analyze the relationship between money availability and risky behaviors we computed odds ratios and 95% confidence intervals through unconditional multiple logistic regression models. Results. Spending more than 10€ weekly was associated with higher likelihood to smoke, binge drink or gamble. Receiving pocket money (rather than receiving money upon request) was related to higher likelihood to engage in risky behaviors. Conclusions. Pocket money may have a negative impact on adolescents, particularly with a substantial amount of money. More research is needed to understand why providing money only if needed may serve as a protective factor against risky behaviors

Advances in modelling of biomimetic fluid flow at different scales

The biomimetic flow at different scales has been discussed at length. The need of looking into the biological surfaces and morphologies and both geometrical and physical similarities to imitate the technological products and processes has been emphasized. The complex fluid flow and heat transfer problems, the fluid-interface and the physics involved at multiscale and macro-, meso-, micro- and nano-scales have been discussed. The flow and heat transfer simulation is done by various CFD solvers including Navier-Stokes and energy equations, lattice Boltzmann method and molecular dynamics method. Combined continuum-molecular dynamics method is also reviewed

Evaluation of the CHF, with special regard to the CHFR in the hot channel of the RBMK Smolensk 3 plant

The EC- (European Commission) EURATOM TACIS project 30303 aims at safety evaluation of VVER-1000 (Russian Design, Gidropress, pressurized water reactor) and of RBMK (Russian design, NIKIET, boiling water cooled, graphite moderated nuclear reactor). Safety improvements for those reactors are also expected from the project. About 50 scientists of various nationalities (primarily Russian and Italian) contributed to the project for around 5 years. A variety of experimental and computational activities was performed. Several hundred reports were issued within a suited Quality Assurance (QA) framework and many scientists contributed to each report (only responsible authors identified here). The present document deals with the evaluation of the Critical Heat Flux (CHF) in the boiling channels of RBMK characterized by a 8m active length and (nearly) triangular pitch of rods

Ebollizione in convezione forzata in condizioni di microgravità

Rendiconti Accademia Nazionale delle Scienze detta dei XL Memorie di Scienze Fisiche e Natural