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On 20 February 2023, the OntoCommons team will present the strategic objectives of ontology-driven data documentation for industry commons through a dedicated webinar.

We introduce a new role in the field of semantic knowledge management which we call Translator in Knowledge Management for Innovation. Our interest is in the role helping to shape purposeful and traceable communication in materials and manufacturing industries and, thus, to make knowledge become managed knowledge that is actionable for innovation. We envisage that such communication will lead to harmonisation across the boundaries of the wide range individual domains and disciplines interacting in these fields. Current divisions and silos mean that there is a huge untapped value not just in terms of ‘lost’ data but also stakeholder knowledge, which currently is not well captured. The Knowledge Management Translator will work with materials and manufacturing domain experts as well as data scientists and knowledge engineers to shape data in order to express knowledge. The job of the Knowledge Management Translator is to bring together and orchestrate people, tools, and processes to achieve this. To define this new role, we build on existing Technology Translator roles such as the Materials Modelling Translator and the Analytics Translator. We also tap into the professional experience of all the authors who are actively researching, practising, or working with ontologies, materials modelling, and data sciences. Therefrom we create an ideal persona and assign a variety of tasks and required skills to them. We provide a template for a structured approach to Knowledge Management Translation, as a process broken down into six steps, adapted from the Materials Modelling Translation Guide. Given the wide range of tasks and skills required, hardly any person today will be able to fulfil all of these on their own. Hence, Translators will work in teams, also including some client-internal and third-party consultants. This sounds prohibitively expensive but may become reality once the clients create more and more data management roles, and once universities train data management skills, and once management of data related to materials and manufacturing will facilitate systematic sustainability assessment. Having the economic viability in mind, we suggest some early paths to success that do not require the full range of experts. We also highlight that clients need to have a certain maturity level regarding data readiness to enable a fruitful interaction, and with increasing data and knowledge management maturity clients will profit from implementing the role in their company. We discuss some current gaps and challenges for this new role and outline the next steps to make the Knowledge Management Translator role a reality. We aim to consolidate expert knowledge and further develop the role in the context of the H2020 OntoCommons project, to offer budding Knowledge Management Translators continuous professional development opportunities.

Semantic enhancement of existing metadata schemas for data documentation and exchange is presented, to cover the fundamental concepts needed within the DOME4.0 project. Concepts from the DCAT RDF vocabulary (and from the RDF schema which DCAT depends on) for the description of datasets and data services (and catalogues) have been mapped in an enriched semantic framework provided by the Elementary Multiperspective Material Ontology (EMMO). This is done by imposing constraints that enable the usage of the original DCAT concepts into an OWL 2 DL framework. A mapping ontology from DCAT together with an ontology extension of the EMMO in order to deal with specific data concepts is provided in a public repository. Results of this mapping will be ported into the OntoCommons Top Reference Ontology. This will make it usable also by other ontological approaches (e.g. BFO, DOLCE). This work offers innovative value via (i) providing the means to bridge between the state of the art widely used top level ontologies and widely used web standard metadata schemas/vocabularies; and (ii) presenting a novel means of ontologising such metadata schemas and bringing them to a high-level semantic logic. A first example of combination of syntactic description of data and semantic mapping, is also provided.

This document will provide recommendations about (1) the definition of interoperability scenarios, including potential taxonomies for Open Simulation Platforms (i.e. an environment which provides open standards for integration and interoperability of materials models) depending on the type and level of integrations within the components; (2) the use of an ontology as standard reference for the representation of concepts and data in an interoperable environment; (3) the use of the EMMO for the achievement of syntactic and semantic interoperability.

The effects of different operating pressures on the temperature and current profile of a 150A plasma arc cutting torch are investigated using modelling in order to provide useful information on the heat transfer mechanisms and on the position and magnitude of the temperature peaks, with the final aim to provide some new insights on the erosion mechanisms.

The present study aims at producing Al-based nanocomposites reinforced with low fractions of ceramic nano-reinforcement produced by thermal plasma, evaluating the strengthening effects induced by their addition to the idely used A356 (Al-Si-Mg) cast aluminum alloy. Nanoparticles were produced using a lab-scale RF inductively coupled thermal plasma system designed by simulation as to optimize the plasma operating conditions and reactor geometry. During the casting route, ultrasonic treatment of the melt was performed to better disperse the reinforcing particles into the matrix. Ceramic spherodized microparticles were also synthesized and micro-reinforced Al-matrix composites were produced with the same route for comparison. Microstructural characterization of the cast samples was carried out by optical and scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) analysis. BET analysis was also used for powder characterization. Hardness tests were performed to assess the enhancement in mechanical properties obtained by addition of nanoparticles with respect to both the microparticle reinforced and unreinforced Al-Si-Mg matrix.

Electrode and nozzle erosion mechanisms in plasma arc cutting processes of mild steel have been studied while designing a prototype mono-gas plasma torch, operating in the range 25-160 A. The correlation between the distribution of different quantities inside the plasma chamber and the erosion mechanisms of the hafnium emitter surface and of the nozzle inner surfaces have been investigated by means of a 2D ANSYS FLUENT-based numerical model, with the final aim of optimizing the overall performances of the prototype. Modelling and numerical simulation have allowed better understanding of the physical phenomena evidenced by experimental results and have suggested successful design solutions for consumables (in particular nozzle, electrode and primary gas diffusers). The correlation between the results of experimental tests and numerical simulations has proven useful in overcoming the critical aspects initially pointed out, significantly improving the expected lifetime of consumables. Results have been analyzed with respect to plasma behaviour, and conclusions have been drawn, concerning the powerfulness of numerical simulation as a tool for designing plasma cutting torches.

A 3-D time-dependent simulation of a laboratory scale inductively coupled thermal plasma torch system has been carried out to investigate unsteady turbulent flow patterns which may arise in the reaction chamber as a consequence of a sharp expansion of the gas at the torch outlet. A Large Eddy Simulation (LES) model has been used to predict the instantaneous flow field, without any time filtering as done in the RANS models (for example k- or RSM).

Transferred arc plasma torches are widely used in industrial cutting process of metallic materials because of their ability to cut a wide range of metals and because of the very high productivity that can be achieved with this technology. Various experimental and computational activities will be reported here and in particular: high speed imaging of transient phenomena and Schlieren photography in Plasma Arc Cutting (PAC), experimental analysis of the behavior of high current electrodes in PAC during first cycles and plasma modelling and numerical simulation as a useful tools for the design and optimization of these kinds of devices. Proceedings of the XVIII International Conference on Gas Discharges and Their Applications-GD 2010, (Editor Prof. K.-D. Weltmann), GD 2010 Local Organizing Committee, Greifswald, 2010, pp. 18-25 (ISBN: 0-9539105-4-7).

The aim of this work is to investigate, by means of a 3-D FLUENT© based numeri-cal model the fluid flow and temperature distribution of a plasma transferred arc discharged inside a manual plasma cutting torch. The detailed gas injection sections and of shield geome-try are included in the domain as well.

The aim of this work is to investigate by means of a 3D time-dependent numerical model a particle stream inside a DC non-transferred arc plasma torch for plasma spraying, in order to analyze the influence of the plasma jet cold gas entrained eddies on the particle behavior and to understand the mechanisms that can lead to a fluctuating and non homogeneous heating of the particle stream.

3-D simulations of a radio frequency ICP torch with reaction chamber have been performed to investigate the thermal and fluid-dynamic behaviour of the discharge under different realistic operating conditions taking into account powder injection from the tip of the probe, using customized CFD commercial code FLUENT.

The behaviour of hafnium cathodes at the beginning of their service life when operating at high current levels in the plasma arc cutting (PAC) process has been experimentally investigated with the final aim of understanding the phenomena that take place during those initial piercing and cutting phases and optimizing the initial shape of the surface of the emissive insert exposed to plasma atmosphere.

High speed camera (HSC) imaging has been used to investigate pilot arcing and piercing process phases in plasma arc cutting of mild steel (MS) and stainless steel (SS) plates with dual gas torches in various operating conditions, providing new insight of the process and highlighting some interesting phenomena. For pilot arcing, HSC imaging has been used to estimate the influence of different operative parameters (arc current, plasma pressure and swirl strength) on the shape of pilot arc and on the type rotational motion of the pilot arc loop attachment on the nozzle tip, to describe the behaviour of the arc and of the emissive surface during different phases of pilot arcing and to track trajectories and velocities of hafnium particles emitted from the electrode during that phase. As regards the piercing process phases, HSC imaging allowed to study phenomena that take place during double arcing and the arc behaviour during piercing of SS thick plates.

Thermal plasma processes and devices have been extensively studied and designed using modeling approach in the last two decades. Still, knowledge of thermodynamic and transport properties is one of the major needs in the modeling of thermal plasma processes. Computation of these properties is usually carried out through the approximated solution of the Boltzmann’s equation using the Chapman–Enskog’s method. While local thermodynamic equilibrium (LTE) was assumed in the past calculations, the development and use of more sophisticated plasma diagnostics have shown that this assumption often fails in thermal plasmas: for thermal non-equilibrium plasmas, the kinetic electron temperature Te is then assumed to be different from that of heavy species Th, chemical equilibrium being achieved. Nonequilibrium thermodynamic and transport property calculations of argon, nitrogen and oxygen plasmas at atmospheric pressure for electron temperature up to 45,000 K are here presented. Transport properties have been obtained using numerical codes developed by the authors which implement the Devoto’s electron and heavy particles decoupling approach. Variation of composition, specific volume, specific enthalpy, specific heat, thermal conductivity, electrical conductivity and viscosity as a function of electron temperature and different degrees of non-equilibrium are reported. Results are compared with available data from published reports to check the accuracy of the developed codes.

The aim of this work is to investigate by means of a 3D time-dependent numerical model the plasma flow and heat transfer inside a DC non-transferred arc plasma torch operating at atmospheric pressure [1-6], using a customized version of the CFD commercial code FLUENT©. Unsteady flow and heat transfer equations are solved with coupled electromagnetic ones, for an Ar optically thin plasma under conditions of LTE. Cathode and anode regions are taken into account in a simplified way, neglecting the non equilibrium effects of the sheath region. The attachment and detachment of the discharge on the anode wall as a result of the drag of the flow field is predicted imposing an uniform zero potential condition on the wall. Turbulence effects are taken into account by means of a Large Eddy Simulation (L.E.S.) approach, solving the dynamic behavior of the larger scale eddies outside the torch nozzle. Prediction of particle trajectories and thermal history is performed in order to predict the effect of the cold gas entrained eddies on particle behavior.

Modeling results are presented for different industrial thermal plasma sources using a customized version of the FLUENT© code for 2D and 3D transient simulation with advanced CFD models that take into account turbulence effects using different approaches (Reynolds Stress Model and Large Eddy Simulation), species transport and radia-tion (Discrete Ordinate Model with interaction between radiation and solid surfaces). This modeling tool is very useful for the design and characterization of a wide range of atmospheric pressure thermal plasmas devices and ap-plications. Results will be presented for: 1) Turbulent 3-D modeling of ICPTs showing trajectory and heating history of powders injected in the torch through a carrier gas for spheroidization purposes, together with their effect on the plasma discharge for various geometric, electric and op-erating conditions; the helicoidal coil and the gas injection section of industrial plasma torches are taken into account without geometry simplifications; 2) Time-dependent effects arising in the fluid flow and temperature distribu-tion of a plasma generated in arc discharge twin-torch systems (for example, for hazardous waste incineration) with turbulence effects taken into account using a RANS approach; the effect on the discharge characteristics of using different types of plasma gas (air and Ar/H2 mix-tures), for various geometric and operating conditions is taken into account; 3) 3-D time dependent simulation of the behaviour of DC non-transferred arc torch for plasma spraying without any external assumption on the anode restriking and attachment and insight also on the down-stream expansion of the plasma jet using a LES turbulence model.

The aim of this work is to investigate by means of a 2-D and 3-D FLUENT© based numerical model the behaviour of different types of transferred arc dual gas plasma torches used for cutting of metallic materials [1-8], putting into evidence the physical reasons for the industrial success of various design and process solutions appeared over the last years, such as: secondary gas swirl injections with different directions, various different approaches for the geometry of the plasma chamber, the effect of externally superimposed magnetic fields, the effect of different geometry for efficiently cooling the inner electrode region. Flow and heat transfer equations are solved with coupled electromagnetic ones, for a LTE optically thin plasma, while turbulence phenomena are taken into account by means of a k-ε RNG model [9-11]. Simulations include a prediction of the thermal behaviour of the solid components of the torch head, including electrode and its hafnium insert, thermal histories and trajectories of particles emitted from it under idealized conditions and the efficiency of nozzle and electrode cooling systems in various operating conditions including gas mixtures (O2/air, H35/N2, N2/N2). Radiation heat transfer to the surface of the components is included in the calculation using a customized Discrete Ordinate (DO) model. Simulations of one of the plasma torches here considered are also compared with experimental measurements in order to perform a validation of the model for what concerns pressure values in different regions of the device, regions of the device, nozzle temperature and gas mass flow rate during the working phase.

Advanced Modelling of Thermal Plasmas for Industrial Applications V. Colombo, E. Ghedini Department of Mechanical Engineering (D.I.E.M.) and Research Center for Applied Mathematics (C.I.R.A.M.) Università di Bologna, Via Saragozza 8, 40123 Bologna, Italy Modeling results are presented for different industrial thermal plasma sources using a customized version of the commercial code FLUENT capable of 2D and 3D transient simulation with advanced CFD models that take into account turbulence effects using different approaches (Reynolds Stress Model and Large Eddy Simulation), species transport and radiation (Discrete Ordinate Model with interaction between radiation and solid surfaces). Simulations results are presented in order to show the capabilities of this modeling tool, which is very useful for the design of a wide range of atmospheric pressure thermal plasmas devices and applications, such as: ICPTs with injection of powders for spheroidization purposes (showing the trajectory and heating history of powders injected in the torch through a carrier gas together with their effect on the plasma discharge for various geometric, electric and operating conditions by means of an improved turbulent version of a 3-D previously developed code where the helicoidal coil and the gas injection section of industrial plasma torches are taken into account without geometry simplifications), twin-torch DC transferred arc plasma systems for waste treatment (showing time-dependent effects arising in the fluid flow and temperature distribution of a plasma transferred electric arc discharge generated between two suspended metallic electrodes used inside a plasma furnace for hazardous waste incineration with turbulence effects taken into account using a RANS approach, as well as the effect on the discharge characteristics of using different types of plasma gas (air and Ar/H2 mixtures), for various geometric and operating conditions), DC non-transferred arc torch for plasma spraying (3-D time dependent model to simulate the behaviour of such a device without any external assumption on the anode restriking and attachment and to simulate also the downstream expansion of the plasma jet after the torch nozzle using a LES turbulence model). D. Bernardi, V. Colombo, E. Ghedini, A. Mentrelli, Pure and Applied Chemistry, 77, pp. 359 – 372, (2005). D. Bernardi, V. Colombo, E. Ghedini, A. Mentrelli, T.Trombetti, Czechoslovak Journal of Physics. 54, pp. C489 - C515 (2004). D. Bernardi, V. Colombo, E. Ghedini, A. Mentrelli, T. Trombetti, IEEE Transactions on Plasma Science, 33, pp. 424–425 (2005). D. Bernardi, V. Colombo, E. Ghedini, A. Mentrelli, IEEE Transactions on Plasma Science, 33, pp. 426–427 (2005). D. Bernardi, V. Colombo, E. Ghedini, S. Melini, A. Mentrelli, Three-dimensional time-dependent modelling of magnetically deflected transferred arc, IEEE Transaction On Plasma Science 33, 428-429 (2005). V. Colombo, E. Ghedini, Time Dependent 3-D Simulation of a DC Non-Transferred Arc Plasma Torch: Anode Attachment and Downstream Region Effects, Proc. of the 17th Int. Symp. on Plasma Chemistry-ISPC17 (2005). V. Colombo, E. Ghedini, A. Mentrelli, E. Malfa, 3-D Modelling of DC Transferred arc Twin Torch for Asbestos Inertization. In Nuclear Reactor Physics. A collection of papers dedicated to Silvio Edoardo Corno, Torino, C.L.U.T., pp. 169 - 196 (2005). V. Colombo, E. Ghedini, Time-Dependent 3-D Modelling Of Dc Transferred Arc Twin Torch, High Technology Plasma Processes 9 - HTPP9, St. Petersburg (2006).

Reclaimed glass powders from fluorescent lamps are sieved in two particle size ranges after Hg purification and are subjected to thermal plasma in-flight treatment by injection into the discharge of a Tekna PL-35 plasma torch and reaction chamber as part of a source operated at 3MHz with a maximum power of 25kW, with Ar as plasma and carrier gas and N2 as sheath gas. The sieved powders and the plasma treated ones have been characterized by powder XRD and particle size analysis in order to verify if the plasma treatment can induce modification in the minera-logical and physical characteristics. The spherical shape of the particles has been analyzed by scanning electron mi-croscopy. Moreover, this technique has allowed to verify if the plasma treatment can induce modification of the (qualitative) chemical composition of the powder. Results for various operating conditions and injection probe posi-tions are presented. The spherical powders have been then introduced in thermoplastic polymers in place of glass spheres usually used, and the results are compared to each others. The samples are characterized by mechanical tests (flexural strength) and microstructural analysis (SEM) in order to verify the differences in materials properties ob-tainable by mean of conventional and plasma assisted processes.

The aim of this work is to investigate by means of a 3-D FLUENT© based numerical model time-dependent effects arising in the fluid flow and temperature distribution of a plasma transferred electric arc discharge generated between two suspended metallic electrodes used inside a plasma furnace for hazardous waste incineration. Flow and energy equations are solved for optically thin Ar plasma under conditions of LTE, while the electromagnetic field equations are solved in their scalar and vector potential form. Electrodes interfaces are taken into account using a simplified approach and their regions are discretized in their detailed design, in order to better understand the effects of their geometries on the discharge behavior. Turbulence effects are taken into account into the model using a RANS approach, as well as the effect on the discharge characteristics of using different types of plasma gas (air and Ar/H2 mixtures), for various geometric and operating conditions. Simulations can also give important information on non-axisymmetric anode attachment under particular operating conditions. Simulations are performed using a customized CFD commercial code, parallelized over a network cluster of double processor calculators in order to use the full capabilities of the 3-D code.