NUMERICAL SIMULATION OF ICE ACCRETION ON AIRFOIL

This work consists in the simulation of the ice accretion in the leading edge of aerodynamic profiles and our proposed model encompasses: geometry generation, calculation of the potential flow around the body, boundary layer thickness computation, water droplet trajectory computation, heat and mass balances and the consequent modification of the geometry by the ice growth. The flow calculation is realized with panel methods, using only segments defined over the body contour. The viscous effects are considered using the Karman-Pohlhausen method for the laminar boundary layer. The local heat transfer coefficient is obtained by applying the Smith-Spalding method for the thermal boundary layer. The ice accretion limits and the collection efficiency are determined by computing water droplet trajectories impinging the surface. The heat transfer process is analyzed with an energy and a mass balance in each segment defining the body. Finally, the geometry is modified by the addition of the computed ice thickness to the respective panel. The process by repeating all the steps. The model validation is done using a selection of problems with experimental solution, CIRA (the CESAR project). Hereinafter, results are obtained for different aerodynamic profiles, angles of attack and meteorological parameter

Theoretical and numerical method in aeroacoustics

The paper deals with the mathematical and numerical modeling of the aerodynamic noisegenerated by the fluid flow interaction with the solid structure of a rotor blade.Our analysis use Lighthill’s acoustic analogy. Lighthill idea was to express the fundamental equationsof motion into a wave equation for acoustic fluctuation with a source term on the right-hand side. Theobtained wave equation is solved numerically by the spatial discretization. The method is applied inthe case of monopole source placed in different points of blade surfaces to find this effect of noisepropagation

Frame and framing: a theory-based investigation into frame as an instrument for landscape architecture

In this paper, I introduce the concept of the frame. The mechanisms of framing are a strategic and conceptual tool for dealing with the complexities of place in terms of site specificity.  Starting from both a theoretical understanding of the frame in terms of what it does rather than what it is, and from a specific site — the territory surrounding the Palace of the Parliament in Bucharest, Romania — I investigate ways of working with a contested territory in a site specific, open-ended way. As the locus of a large-scale urban project for a new civic centre initiated in 1984 by Ceausescu and interrupted by the revolution of 1989, this territory is fixed in both scale and determination. The mechanisms of framing provide the starting point for rethinking the site through framing, in order to uncover, draw out, and reconfigure its specificities, providing a structure for a wide range of place-making practices to unfold

Frame and framing: a theory-based investigation into frame as an instrument for landscape architecture

In this paper, I introduce the concept of the frame. The mechanisms of framing are a strategic and conceptual tool for dealing with the complexities of place in terms of site specificity.  Starting from both a theoretical understanding of the frame in terms of what it does rather than what it is, and from a specific site — the territory surrounding the Palace of the Parliament in Bucharest, Romania — I investigate ways of working with a contested territory in a site specific, open-ended way. As the locus of a large-scale urban project for a new civic centre initiated in 1984 by Ceausescu and interrupted by the revolution of 1989, this territory is fixed in both scale and determination. The mechanisms of framing provide the starting point for rethinking the site through framing, in order to uncover, draw out, and reconfigure its specificities, providing a structure for a wide range of place-making practices to unfold

Adapting a geographical information system-based water resource management to the needs of the Romanian water authorities

Background, aim, and scope: The need for global and integrated approaches to water resources management, both from the quantitative and the qualitative point of view, has long been recognized. Water quality management is a major issue for sustainable development and a mandatory task with respect to the implementation of the European Water Framework Directive as well as the Swiss legislation. However, data modelling to develop relational databases and subsequent geographic information system (GIS)-based water management instruments are a rather recent and not that widespread trend. The publication of overall guidelines for data modelling along with the EU Water Framework Directive is an important milestone in this area. Improving overall water quality requires better and more easily accessible data, but also the possibility to link data to simulation models. Models are to be used to derive indicators that will in turn support decision-making processes. For this whole chain to become effective at a river basin scale, all its components have to become part of the current daily practice of the local water administration. Any system, tool, or instrument that is not designed to meet, first of all, the fundamental needs of its primary end-users has almost no chance to be successful in the longer term. Materials and methods: Although based on a pre-existing water resources management system developed in Switzerland, the methodological approach applied to develop a GIS-based water quality management system adapted to the Romanian context followed a set of well-defined steps: the first and very important step is the assessment of needs (on the basis of a careful analysis of the various activities and missions of the water administration and other relevant stakeholders in water management related issues). On that basis, a conceptual data model (CDM) can be developed, to be later on turned into a physical database. Finally, the specifically requested additional functionalities (i.e. functionalities not provided by classical commercial GIS software), also identified during the assessment of needs, are developed. This methodology was applied, on an experimental basin, in the Ialomita River basin. Results: The results obtained from this action-research project consist of a set of tangible elements, among which (1) a conceptual data model adapted to the Romanian specificities regarding water resources management (needs, data availability, etc.), (2) a related spatial relational database (objects and attributes in tables, links, etc.), that can be used to store the data collected, among others, by the water administration, and later on exploited with geographical information systems, (3) a toolbar (in the ESRI environment) offering the requested data processing and visualizing functionalities. Lessons learned from this whole process can be considered as additional, although less tangible, results. Discussion: The applied methodology is fairly classical and did not come up with revolutionary results. Actually, the interesting aspects of this work are, on the one hand, and obviously, the fact that it produced tools matching the needs of the local (if not national) water administration (i.e. with a good chance of being effectively used in the day-to-day practice), and, on the other hand, the adaptations and adjustments that were needed both at the staff level and in technical terms. Conclusions: This research showed that a GIS-based water management system needs to be backed by some basic data management tools that form the necessary support upon which a GIS can be deployed. The main lesson gained is that technology transfer has to pay much attention to the differences in existing situations and backgrounds in general, and therefore must be able to show much flexibility. The fact that the original objectives could be adapted to meet the real needs of the local end-users is considered as a major aspect in achieving a successful adaptation and development of water resources management tools. Time needed to setup things in real life was probably the most underestimated aspect in this technology transfer process. Recommendations and perspectives: The whole material produced (conceptual data model, database and GIS tools) was disseminated among all river basin authorities in Romania on the behalf of the national water administration (ANAR). The fact that further developments, for example, to address water quantity issues more precisely, as envisaged by ANAR, can be seen as an indication that this project succeeded in providing an appropriate input to improve water quality in Romania on the long ter

Social Enterprises - Viable Solutions for People with Disabilities?

Social enterprises are possible solutions for the integration of people with disabilities, one of the most discriminated social categories in the labor market. Through an in-depth analysis of articles related to this field, published in scientific journals in the last 5 years, we want to investigate the role of social entrepreneurship in increasing the employment of people with disabilities. Content analysis has identified key benefits, such as increased living standards and a lower risk of dependence on social benefits. At the same time, there are disadvantages such as: increased segregation and isolation or reduced chances of integration into the free labor market. This paper contributes to the broadening of knowledge about social enterprises that employ people with disabilities, opening new possible directions of research. Second, the paper highlights practical implications for the inclusion of people with disabilities in the labor market

L'epidèmia d'Eugène Ionesco

La Facultat de Filosofia i Lletres de la UAB publica, des de principis del confinament pel Covid-19, una sèrie de píndoles en forma de breu article, sota el títol 'Llibres i música en temps de desassossec', on es convida al lector a conèixer diferents suggeriments per a la lectura o l'audició de música, que ajudin a millorar l'estat d'ànim i aportin coneixement en moments difícils i d'incertesa per a tots. A 'Llibres i música en temps de desassossec' es poden llegir textos de professors i professores de la FacultatText publicat com a notícia a la web de la Facultat de Filosofia i Lletres de la Universitat Autònoma de Barcelona el 17/04/202

Layered Composites Based on Recycled PET/Functionalized Woven Flax Fibres

Extended Abstract Plastic waste is generated by a variety of sources including packaging, automotive, consumer goods, electrical and electronics industries, leading to a significant growth in the volume of waste and the impetuous need to reduce it The paper aims at developing new layered composite materials based on recycled thermoplastic polymer (PETpolyethylene terephthalate) from the food industry reinforced with woven flax fiber functionalized with nano (micro) particles of titanium or alumina and testing the composite in terms of physico-mechanical (tensile strength, bending, shock, etc.), morphological (SEM), structural (FTIR), and thermal (Vicat) properties. Based on this technology, the new composite will exhibit improved physical, mechanical and thermal properties, as well as resistance to mold attack. In this regard, in the first stage, the surface of flax fibers were chemically modified using aluminum (AlCl3), and titanium (titanium butoxide) precursors followed by precipitation. The woven flax whose surface was functionalized with nano (micro) alumina or TiO2 particles were subsequently used to obtain layered composite materials. Layered composite materials were obtained by alternating functionalized / not functionalized woven flax fiber with sheets made from recycled PET. The recycled PET sheets and layered composites based on recycled PET and functionalized / not functionalized woven flax fiber were obtained by press molding using an electrical press at the following optimum parameters: plate temperature -254ºC, preheating time -8 min; pressing time -2 min; cooling time -15 min; pressing force -100 kN. Special attention must be paid to the pre-drying process (at 100-110ºC) to remove adsorbed water. In the absence of the pre-drying operation, the resulting sheets exhibit holes, porosity and discontinuities, making them unusable for the development of layered composite materials. Physical, mechanical and thermal analyses results for specimens of layered composite materials based on recycled PET / functionalised woven flax fiber show significantly improved values compared with the control samples obtained from recycled PET / not functionalized flax fiber. Improved mechanical and thermal properties are due to links developed at the woven flax fiber / polymer phase interphase. Results have also been confirmed by SEM, while the degree of adhesion and the interpenetration of polymer phase / woven flax fiber are superior in the case of composites made of functionalized flax fibers in comparison with the unfunctionalized ones