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As first proposed by Madelung in 1926, the analogy between quantum mechanics and hydrodynamics has been known for a long time; however, its potentialities and the possibility of using the characteristic equations of quantum mechanics to simulate the behavior of inviscid fluids have not been thoroughly investigated in the past. In this methodology, the incompressible Euler equations are thus substituted by the Schrödinger equation, turning a quasi-linear Partial Differential Equation into a linear one, an algorithm known in the literature as Incompressible Schrödinger Flow. Previous works on the subject used the Fast Fourier Transform method to solve this problem, obtaining promising results, especially in predicting vortex dynamics; this paper aims to implement this novel approach into a Finite Element framework to find a more general formulation better suited for future application on complex geometries and on test cases closer to real-world applications. Simple case studies are presented in this work to analyze the potentialities of this method: the results obtained confirm that this method could potentially have some advantages over traditional Computational Fluid Dynamics method, especially for what concerns computational savings related to the required time discretization, whilst also introducing new aspects of the algorithm, mainly related to boundary conditions, not addressed in previous works. [ABSTRACT FROM AUTHOR]

This paper provides a detailed description of the Photovoltaic Assembly (PVA) and, in particular, how the extreme environmental and operative requirements of the Exomars missions are met. “Exomars” is a program established by the European Space Agency to investigate the Martian environment and to validate new technologies in view of future Mars exploration missions. The first mission will be launched in 2016 and will carry a spacecraft composed of the Trace Gas Orbiter (TGO) and the Entry, descent and landing Demonstrator Module (EDM). The second mission is scheduled on year 2018 and will carry a rover vehicle. Leonardo PVA contribution is on either the TGO, Carrier and Rover vehicle solar arrays. Moreover we were deeply involved in the design of the power conditioning and distribution electronics of the TGO leveraging on our Power Management and Distribution heritage for scientific platforms. As far as Exomars SA’s (Solar Array) are concerned, they are significantly different: the TGO is based on two deployable wing system, whose attitude is controlled by the SADM. Each wing comprehends two panels. The Rover vehicle solar array assembly (SAA) is made of a fixed panel and four deployable (primary and secondary) panels. This SAA is unique with respect to standard deployable systems because of the motor deployment control and trimming possibilities during Martian soil exploration. Each of these missions imposed major design challenges: for the TGO the aero braking maneuvers will cause a significant dissipation of the kinetic energy leading to a solar array temperature increase up to +175°C on the rear face, while +135°C on the front (active) face. On the other hand, during the cruise phase the same PVA will experience extreme cold temperatures down to -209°C. For the rover SAA the biggest challenge is related to surviving Mars planet environment (i.e. dust, wind and charge accumulation) and the associated mechanical and electrical constraints. We duly considered the experience gained by NASA-JPL on previous Mars lander missions and the selected technical solutions, all taken from the European heritage, represent the evolution to what already successfully flown. Finally the bio burden and planetary protection requirements are also not a standard in SA field. A special manufacturing, assembly and test sequence will be implemented to capitalize our previous experience on the Mars drill tool development. For both the arrays European PVA technology was exclusively used: more specifically high efficiency III-V compounds solar cells and a new glass grounding network.

The electrostatic discharge testing on Photovoltaic Assemblies has been thoroughly investigated and performed during the last decade to ensure durability of solar arrays, especially in cases of high power satellites. Leonardo Company together with Aerospazio Tecnologie performed the test for the first time in the framework of Meteosat Third Generation (MTG, a Geostationary satellite of 2.5kW, mounting 3G solar cells) with two goals: the first was to qualify MTG PVA technology against possible ESD occurrences during mission and the second was to characterize the PVA design limits against self-sustained arcs. This paper illustrates the ESD analysis, the test set up preparation and the test results obtained in the framework of MTG ESD test campaign.

The paper deals with the upgrading of the primary distribution networks applying the smart grid strategies. In particular, a new research field is devoted to the application of storage systems for the power quality improvement and the better exploitation of renewable sources. In this context, this work proposes the use of a storage based on lithium-ion batteries for the black start and island operation of a portion of the medium voltage network. The innovation of the idea proposed is related to a soft start of the system that reduces transient overvoltages and transient inrush current components in order to reduce the stress of the system and allow the supply in island through direct current/alternating current converters. Simulations carried out on a dedicated model implemented in real-time digital simulator are reported and analyzed. These tests are the basis for a full-scale prototype installation of the storage in a real Italian network as a part of a big project founded by the Italian Energy Authority. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]