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The integration of oxygen transport membranes in industrial processes can lead to energy and economic advantages, but proof of concept membrane modules are highly necessary to demonstrate the feasibility of this technology. In this work, we describe the development of a lab-scale module through a comprehensive study that takes into consideration all the relevant technological aspects to achieve a prototype ready to be operated in industrial environment. We employed scalable techniques to manufacture planar La0.6Sr0.4Co0.2Fe0.8O3-δ membrane components suitable for the application in both 3- and 4-end mode, designed with a geometry that guarantees a failure probability under real operating conditions as low as 2.2 × 10−6. The asymmetric membranes that act as separation layers showed a permeation of approx. 3 NmL/min/cm2 at 900 °C in air/He gradient, with a remarkable stability up to 720 h, and we used permeation results to develop a CFD model that describes the influence of the working conditions on the module performance. The housing of the membrane component is an Inconel 625 case joined to the membrane component by means of a custom-developed glass–ceramic sealant that exhibited a remarkable thermo-chemical compatibility both with metal and ceramic, despite the appearance of chemical strain in LSCF at high temperature. The multi-disciplinary approach followed in this work is suitable to be adapted to other module concepts based on membrane components with different dimensions, layouts or materials.

The present work focuses on the application of the inverse methods on the small punch test (SPT) in order to predict the behavior of turbine rotor steel upon in-service loading. A numerical framework has been implemented in which the small punch test has been simulated by means of finite element analyses and compared with the experimental results in order to assess the material parameters. The comparison has been carried out relying on the load- displacement curve of the SPT. The material behavior has been represented through an elastic-plastic constitutive law and a micro-mechanical damage model to account for softening and material failure. The assessed material parameters have been employed in the simulation of the tensile test, showing a good approximation of the basic mechanical properties of the material

Overhead power line conductors and ground wires are affected by ice and snow accretion which can easily adhere to their surface, causing the breakage of cables and the collapse of pylons due to excessive weight. In Italy, the main concern is about wet snow: this phenomenon occurs close to zero degrees Celsius with snow density reaching up to 350 Kg/m3. Anti-icing and anti-snow coatings represent a possible strategy to mitigate ice accretion on overhead power line structures. Many works are oriented to achieve anti-icing properties, starting from superhydrophobic coatings or slippery coatings; however, there is a lack of knowledge about the anti-snow behaviour of these surfaces. In this work, aluminium alloy conductor and ground-wire samples were prepared with different coatings, which include hydrophobic, superhydrophobic and slippery surfaces prepared in the laboratory. Characterisations of sample wettability at room and low temperatures and ice adhesion strength were carried out in the laboratory. Anti-snow behaviour was studied in outdoor test facilities in the Italian Alps during several snowfall events. Furthermore, the environmental parameters were also recorded. Two figures of merit were developed to quantify anti-snow behaviour of the samples: one describing the fraction of surfaces covered by snow during the snowfall event and the other representing the maximum accretion load reached on the samples. Results of laboratory and field testing are compared and discussed. Field testing evidenced a promising snowphobic behaviour for all the samples, despite the different anti-icing and wettability properties measured in the laboratory. The mitigation of the phenomenon was found to occur mainly with two different mechanisms: the delay in snow accretion on the surface and/or the early shedding of the snow-sleeve.