Solid Oxide Fuel Cells: Numerical and Experimental Approaches

Solid oxide fuel cell (SOFC) is a promising electrochemical technology that can produce electrical and thermal power with outstanding efficiencies. A systematic synergetic approach between experimental measurements and modelling theory has proved to be instrumental to evaluate performance and correct behaviour of a chemical process, like the ones occurring in SOFC. For this purpose, starting from SIMFC (SIMulation of Fuel Cells) code set-up by PERT-UNIGE (Process Engineering Research Group) for Molten Carbonate Fuel Cells [1], a new code has been set-up for SOFCs based on local mass, energy, charge and momentum balances. This code takes into account the proper reactions occurring in the SOFC as well as new geometries and kinetics thanks to experiments carried out on single cells and stack in ENEA laboratories of C.R. Casaccia and VTT Fuel Cell Lab in Finland. In particular using an innovative experimental setup it has been possible to study experimentally the influence of a multicomponent mixtures on the performance of SOFC and also validate locally a 2-D model developed starting from SIMFC code. The results obtained are good, showing a good agreement between experimental and numerical results. The obtained results are encouraging further studies which allow the model validation on a greater quantity of data and under a wider range of operating conditions

Advances in Vibration Analysis Research

Vibrations are extremely important in all areas of human activities, for all sciences, technologies and industrial applications. Sometimes these Vibrations are useful but other times they are undesirable. In any case, understanding and analysis of vibrations are crucial. This book reports on the state of the art research and development findings on this very broad matter through 22 original and innovative research studies exhibiting various investigation directions. The present book is a result of contributions of experts from international scientific community working in different aspects of vibration analysis. The text is addressed not only to researchers, but also to professional engineers, students and other experts in a variety of disciplines, both academic and industrial seeking to gain a better understanding of what has been done in the field recently, and what kind of open problems are in this area

Production of uniform droplets using membrane, microchannel and microfluidic emulsification devices

This review provides an overview of major microengineering emulsification techniques for production of monodispersed droplets. The main emphasis has been put on membrane emulsification using Shirasu Porous Glass and microsieve membrane, microchannel emulsification using grooved-type and straight-through microchannel plates, microfluidic junctions and flow focusing microfluidic devices. Microfabrication methods for production of planar and 3D poly(dimethylsiloxane) devices, glass capillary microfluidic devices and single-crystal silicon microchannel array devices have been described including soft lithography, glass capillary pulling and microforging, hot embossing, anisotropic wet etching and deep reactive ion etching. In addition, fabrication methods for SPG and microseive membranes have been outlined, such as spinodal decomposition, reactive ion etching and ultraviolet LIGA (Lithography, Electroplating, and Moulding) process. The most widespread application of micromachined emulsification devices is in the synthesis of monodispersed particles and vesicles, such as polymeric particles, microgels, solid lipid particles, Janus particles, and functional vesicles (liposomes, polymersomes and colloidosomes). Glass capillary microfluidic devices are very suitable for production of core/shell drops of controllable shell thickness and multiple emulsions containing a controlled number of inner droplets and/or inner droplets of two or more distinct phases. Microchannel emulsification is a very promising technique for production of monodispersed droplets with droplet throughputs of up to 100 l h−1

Polymer-derived ceramics for energy storage application

Nel presente lavoro si sono prodotte fibre ceramiche (SiOC PDCs) tramite electrospinning e successiva pirolisi di tre differenti poli-organo-silsesquiossani. Tali fibre sono state caratterizzate attraverso l'utilizzo di tecniche quali: microscopio ottico, SEM, TEM, FT-IR e spettroscopia Raman. Infine, si è valutata la performance elettrochimica di tali materiali come elettrodi di un supercondensatore attraverso ciclovoltammetria, carica/scarica galvanostatica e spettroscopia di impedenza

Microstructural influence on dynamic properties of age hardenable FeMnAl alloys

A lightweight castable alloy was sought to reduce the MIL-PRF-32269 class II cast steel perforated armor\u27s weight with the requirement that the material had to be manufactured utilizing existing foundry technology and without incurring large alloy cost increases to meet property requirements. Literature on wrought age hardenable Fe-Mn-Al-C alloys suggested this alloy system could achieve weight reduction through high aluminum concentrations with the highest reported strengths exceeding 2 GPa for a Fe-30Mn-9Al-0.9C composition. Even though ballistic testing had not been conducted on this system, high strain rate data of wrought alloys showed excellent work hardenability; greater than existing ballistic metals. Cast material property information was severely limited, thus, a systematic approach was employed to develop casting and processing techniques and assess related structure property relationships of a nominal silicon modified Fe-30Mn-9Al-0.9C-0.5Mo alloy for ballistic use. Castability was addressed first as this information was crucial for making test coupons and assisting foundries with production of MIL-PRF-32269 ballistic test plates. Four silicon concentrations were investigated for fluidity, microstructure, liquidus, solidus and dendrite coherency point. Silicon was added because it is known to increase fluidity of other ferrous alloys and has also been shown to eliminate a brittle ß-Mn phase in wrought Fe-Mn-Al-C alloys. Of the four silicon modified fluidity compositions, two were selected for heat treat property evaluation on the basis of microstructure. Hardness, strength, and ductility were measured (hardness is the only MIL-PRF-32269 measured property). The alloy with the highest ductility was selected for high strain rate evaluation. The strain rate testing results were the final means to lock in the alloy composition and heat treatment for solid plate ballistic testing. While conducting V₅₀ ballistic testing, phosphorus content was correlated to ballistic impact energy. Further testing was conducted to examine phosphorus, quench sensitivity, and aging Charpy V-Notch effects. The culmination of this thesis work resulted with positive ballistic threat testing revealing the alloy investigated here meets the Army\u27s MIL-PRF-32269 ballistic requirements and reduces P900 weight by 13% --Abstract, page iv

Manual on Pearl Oyster Seed Production, Farming and Pearl Culture

The Central Marine Fisheries Research Institute has developed expertise on various marine fisheries and mariculture technologies over the past several years. Based on this expertise the Institute has been offering regular training courses to officials from State Governments, Universities, ICAR Institutes, Krishi Vigyan Kendras, training institutions, industry and progressive farmers on subjects like marine prawn hatchery, prawn farming, pearl oyster hatchery, pearl oyster culture, pearl culture, edible oyster hatchery, edible oyster farming, seaweed culture and utilisation, SCUBA diving, estimation of marine fish production and stock assessment. The Trainers' Training Centre (TTC) of the CMFRI, Cochin, established in the year 1983, has so far conducted 83 such trainings for 590 personnel from the various maritime states including Pondicherry, Lakshadweep and the Andaman & Nicobar Islands

Design Considerations for a Free Space Transportation and Work Station Capsule

A concept for a low cost, low development risk Work Station Capsule for manned extra-vehicular operations is presented. Requirements for such a capsule are established and a conceptual design is outlined. The result is a low cost design providing the astronaut with improved protection and mobility and the means to make his activities more effective and safer. Operational considerations with emphasis on handling of emergencies are discussed. The authors conclude that such a design represents a highly desirable interim approach as a supplement to safe extra-vehicular operations

Investigation and development of a transverse deflecting structure: a beam separator for ELBE

The thesis described the development of a beam separator device for the ELBE accelerator in Dresden, Germany, facilitating simultaneous operation of multiple secondary user stations. After reviewing deflecting structures, an RF cavity was chosen as the optimal solution. Extensive electromagnetic and multiphysics analysis were conducted to optimize the cavity design. A copper deflecting cavity was manufactured and underwent rigorous high-power testing, successfully meeting the design requirements. The cavity is now ready for installation in the ELBE beamline.In dieser Arbeit wurde die Entwicklung einer Strahlseparatorvorrichtung für den ELBE-Beschleuniger in Dresden beschrieben, die den gleichzeitigen Betrieb mehrerer sekundärer Benutzerstationen ermöglicht. Nach der Prüfung von Ablenkungsstrukturen wurde eine HF-Kavität als optimale Lösung gewählt. Umfangreiche elektromagnetische und multiphysikalische Analysen wurden durchgeführt, um das Design des Hohlraums zu optimieren. Ein Ablenkungshohlraum aus Kupfer wurde hergestellt und strengen Hochleistungstests unterzogen, wobei die Designanforderungen erfolgreich erfüllt wurden