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This paper aims to study the heat transfer phenomenon occurring between heated walls and impinging fuel, showing the strict relationship between cooling effect after impingement and enhancing of wallfilm formation. The study focuses on a fundamental task in terms of pollutant emissions in internal combustion engines, aiming at giving a major contribution to the optimization of energy conversion systems in terms of environmental impact.

The paper is based on experimental campaigns relevant at taking measurements of an impinging spray over a heated wall in a confined vessel. The results, in both qualitative and quantitative terms (measurements of liquid and vapour radial penetration and thickness), are numerically reproduced by a computational model based on a Reynolds Averaged Navier Stokes approach, properly validated through customized sub-models.

The paper provides quantitative results about the agreement between radial penetration and vapour thickness between measurements and simulation, achieved by taking into account the cooling effect determined by the fuel impingement. This validation of the numerical model allows the author to give more considerations about the link between wall temperature and wallfilm formation.

This paper presents an original approach for the simulation of wall heat transfer, by imposing a boundary condition at the wall that may consider the heat conduction and temperature cooling given by fuel impingement in both lateral and normal directions. The classical Dirichlet boundary condition, characterized by imposing a fixed temperature value, is, instead, replaced by an approach based on calculating the unsteady process that couples the heat fluxes between the fluid and the solid material and within the solid itself.

Thermochemical conversion processes are one of the possible solutions for the flexible production of electric and thermal power from biomass. The pyrolysis degradation process presents, among the others, the interesting features of biofuels and high energy density bio-oil production potential high conversion rate. In this paper, numerical results of a slow batch and continuous fast pyrolyzers, are presented, aiming at validating both a tridimensional computational fluid dynamics-discrete element method (CFD–DEM) and a monodimensional distributed activation energy model (DAEM) represents with data collected in dedicated experiments. The purpose of this paper is then to provide reliable models for industrial scale-up and direct design purposes.

The slow pyrolysis experimental system, a batch of small-scale constant-pressure bomb for allothermic conversion processes, is presented. A DEM numerical model has been implemented by means of a modified OpenFOAM solver. The fast pyrolysis experimental system and a lab scale screw reactor designed for biomass fast pyrolysis conversion are also presented along with a 1D numerical model to represent its operation. The model which is developed for continuous stationary feeding conditions and based on a four-parallel reaction chemical framework is presented in detail.

The slow pyrolysis numerical results are compared with experimental data in terms of both gaseous species production and reduction of the bed height showing good predictive capabilities. Fast pyrolysis numerical results have been compared to the experimental data obtained from the fast pyrolysis process of spruce wood pellet. The comparison shows that the chemical reaction modeling based on a Gaussian DAEM is capable of giving results in very good agreement with the bio-oil yield evaluated experimentally.

As general results of the proposed activities, a mixed experimental and numerical approach has demonstrated a very good potential in developing design tools for pyrolysis development.

In the recent years the interest toward the use of biomass as a fuel for energy conversion, along with the continuous tightening of regulations, has driven the improvement of accurate design techniques which are required to optimize the combustion process and simultaneously control pollutant emissions. In this paper the use of a 3D Computational Fluid Dynamics approach is analyzed to that aim by means of an application to an existing 50 MW biomass fixed-bed combustion furnace fueled by grape marc. The paper aims to discuss these issues.

The studied furnace is an interesting example of biomass utilization as it may integrate biomass with organic residual by an industrial process. The numerical model has been implemented into an OpenFOAM solver, with an Eulerian-Lagrangian approach. In particular, the fully 3D approach here presented, directly solves for the gas and solid evolution in both the combustion bed and the freeboard. Special care has also been devoted to the treatment of radiating fluxes, having a remarkable influence, again, on the bed evolution.

Results have been compared to experimental data in terms of temperature showing a good agreement. Further comparisons have been done with literature available data for a similar power size biomass furnace showing reasonable similarities.

Emission formation processes in a biomass furnace are dealt with in this paper. The innovation lies in the use of a fully 3D numerical approach, that is validated with regard to temperature measurements gathered in a multi-MW experimental furnace.

Looks at the first 100 years of Italian cinema examining its role in Italy’s recent history. Provides a bibliography of major film directors, Italian cinema sources, reference works, histories, themes, theory and criticism and articles in journals.

This essay aims at retracing the intellectual and biographical events of the economist Gino Arias (1879–1940), examining more in detail the two seasons at the opposite ends of his life: the early one that saw him considerably committed to the Zionist cause and the one that, thirty years later, would force him to confront the racial laws of the Fascist regime.

Despite the seeming tragic continuity of these two phases, Arias’s case is a real historiographical paradox since, over the long span between the opposite ends of his biography, not only did he distance himself from the Zionist movement, but he also gradually laid the foundations for his upcoming and immediate dedication to Fascism; indeed, within the Fascist regime he would stand out as an authoritative and influential theorist of corporatism, the institutional solution Mussolini tried to exploit to organize the national economic life.

After carefully examining Arias’s early contributions to the Zionist cause (that include the establishment of the Florentine Zionist Group and that led him toward strongly nationalistic stances), this essay sums up Arias’s intellectual biography during the next years and then, thanks to unprecedented documents from the Italian Ministry of Interior, closely looks into his fate after his conversion to Catholicism in 1932 and up against the racial laws of 1938, as well as into his attempts to escape persecution. A few final observations will then try to highlight the dramatic exemplarity of his case.

This chapter provides a list and a brief description of files and documents where the name of Piero Sraffa is mentioned and are currently kept at the Archivio Centrale dello Stato and at the Archivio Storico Diplomatico. For each file or document we provide indication of the reference number where it is conserved and a transcription of one or two of the relevant documents out of more than 500 which have been located. The purpose of the chapter is to illustrate the results of archival research of the last decade, including more recent findings, and furnish a groundwork for further research, which may throw further light on documents already known to us, and lead to the discovery of new documents or information, so as to provide a better basis for the reconstruction of the biography of Piero Sraffa and of people whose lives entwined with his – Antonio Gramsci certainly ranking high among them.