Simulation of linear Switched Reluctance Motor drives

This paper presents a simulation model of linear switched reluctance motor drives. A Matlab-Simulink environment coupled with finite element analysis is used to perform the simulations. Experimental and simulation results for a double sided linear switched motor drive prototype are reported and compared to verify the simulation model.Postprint (published version

Two-phase linear hybrid reluctance actuator with low detent force

In this paper, a novel two-phase linear hybrid reluctance actuator with the double-sided segmented stator, made of laminated U cores, and an interior mover with permanent magnets is proposed. The permanent magnets are disposed of in a way that increases the thrust force of a double-sided linear switched reluctance actuator of the same size. To achieve this objective, each phase of the actuator is powered by a single H-bridge inverter. To reduce the detent force, the upper and the lower stator were shifted. Finite element analysis was used to demonstrate that the proposed actuator has a high force density with low detent force. In addition, a comparative study between the proposed linear hybrid reluctance actuator, linear switched reluctance, and linear permanent magnet actuators of the same size was performed. Finally, experimental tests carried out in a prototype confirmed the goals of the proposed actuator.Peer ReviewedPostprint (published version

Linear Switched Reluctance Motors

This chapter deals with linear switched reluctance machines (LSRMs). Linear switched reluctance machines are the counterpart of the rotary switched reluctance machine (SRM), and now they have aroused great interest in the field of electrical machines and drives. In this chapter, first, a mathematical model is presented, and then a procedure for the design of this kind of machines is proposed. Next, a linear switched reluctance force actuator, based on the before designed procedure, is simulated. In addition, experimental proofs of the goodness of the design process and of the accuracy of the simulation of the linear switched reluctance force actuator are given

Comparison of mechanical and electrical characteristics of various polymers blended with ground tire rubber (GTR) and applications

The massive manufacture of tires and the di culty of reducing the stocks of used tires is a serious environmental problem. There are several methods used for recycling wasted tires, one of which is mechanical crushing, in which vulcanized rubber is separated from steel and fibers, resulting in a ground tire rubber (GTR). This can be used in applications such as insulation for footwear work. The aim of the present investigation is to evaluate the use of the GTR when it is mixed with several types of polymer matrix by means of measuring its dielectric and mechanical properties of the resulting composites (polymer + GTR). The analysis is carried out using seven polymeric matrices mixed with di erent GTR concentrations. With the present study, it is intended to propose a way to reuse the tires out of use as an industrial work footwear insulation, by demonstrating the feasibility of the properties analyzedPeer ReviewedPostprint (published version

Study and characterization of the dielectric behavior of low linear density polyethylene composites mixed with ground tire rubber particles

The waste rubber vulcanizate, on account of its stable, cross-linked and three-dimensional structural arrangement, is difficult to biodegrade. Thus, the ever-increasing bulk of worn-out tires is a serious environmental issue and its safe disposal is still a challenging task reported widely by the scientific community. The rubber materials, once they end their useful life, may present difficulties to be reused or recycled. At present, only one tire recycling method is used, which involves grinding and separating steel and fibers from vulcanized rubber, and then using rubber for industrial applications, such as flooring, insulation, footwear. In this paper, a new compound material is presented from a base of reused tire powder (Ground Tire Rubber: GTR) as a mixer and linear low-density polyethylene (LLDPE) as a matrix. The reused tire powder, resulting from grinding industrial processes, is separated by sieving into just one category of particle size (<200 µm) and mixed with the LLDPE in different amounts (0%, 5%, 10%, 20%, 40%, 50% and 70% GTR). Due to the good electrical properties of the LLDPE, this study’s focus is settled on the electrical behavior of the obtained composites. The test of the dielectric behavior is carried out by means of DEA test (Dynamic Electric Analysis), undertaken at a range of temperatures varying from 30 to 120 °C, and with a range of frequencies from 1 to 102, to 3·106 Hz, from which permittivity, conductivity, dielectric constant and electric modulus have been obtained. From these experimental results and their analysis, it can be drawn that the additions of different quantities of GTR to LLDPE could be used as industrial applications, such as universal electrical cable joint, filler for electrical applications or cable tray systems and cable ladder system.Peer ReviewedPostprint (published version

Ground Tire Rubber recycling in applications as insulators in polymeric compounds according to spanish UNE standards

In the present research, we investigated the conceivable outcomes of using ground tire rubber (GTR) particle polymeric blends. Special methods of restoring tires that are no longer in use include GTR retreading, GTR blending destined for recycling to attain raw substances utilized in other industrial application production processes, and the valorization of GTR for power/energy generation. The recycling of end-of-life tires enables the recovery of rubber, steel, and fibers, all of which are valid on the market as raw materials to be used for other processes. There are methods to recycle GTRs in a clean and environmentally friendly way. In the present research, several industrial applications of GTR polymer blends were developed and compared with standard values from the Spanish Association for Standardization (UNE) and the International Electrotechnical Commission (IEC). In order to analyze the viability in many of the industrial applications selected, certain compounds obtained from the GTR polymer blends were analyzed regarding their use in nine low requirement insulator applications. The research and analysis developed in this manuscript used standard values from the UNE and IEC, and these standard values were compared with the test values. The obtained results were used to provide an application list that could be helpful for industrial applications. In this research, the pre-owned polymers were as follows: polypropylene (PP), high-density polyethylene (HDPE), polystyrene (PS), acrylonitrile butadiene-styrene (ABS), ethylene vinyl acetate (EVA), polyvinyl chloride (PVC), and polyamide (PA). The filler used was GTR with particle sizes lower than 200 microns. The amounts of GTR particles in the compound materials were 0% (raw polymer), 5%, 10%, 20%, 40%, 50%, and 70% (the latter being found in polymeric blends). We discovered six plausible modern applications of GTR polymer blends as indicated by the UNE and IEC standards.Peer ReviewedPostprint (published version

Tourist attitudes towards water use in the developing world: A comparative analysis

This paper examines tourists' attitudes towards water use based on comparative data from interviews with tourists in Zanzibar, The Gambia and Dominican Republic. Unsustainable water use, accentuated by climate change, threatens access to water which potentially forms a source of conflict between tourists, tourism businesses, residents and the environment. Additionally it raises issues about rights of access to water. The results emphasise the actual nature and scale of tourist use of water and their lack of awareness of the impacts of this use on the local environment and community. This lack of awareness becomes an added indicator of the growing unsustainability of tourism in certain destinations and needs to be considered alongside the longer-term scenarios of climate change. © 2014 Elsevier Ltd

Influence on the mechanical properties of various polymeric composites reinforced with GTR particles

Un problema medioambiental grave, que nos afecta a los países industrializados desde hace años, lo cons-tituye el uso masivo de neumáticos, los cuales una vez utilizados, generan grandes existencias de ma-terial de residuo. Un método habitual para procesar estos neumáticos utilizados pasa por la trituración mecánica, en la cual se separan la fibra, del acero y del caucho. Este artículo incide en la reutilización del caucho obtenido de estos neumáticos, también llama-do GTR (Ground Tires Rubber), mediante su mezcla con diversos compuestos poliméricos de uso común en la industria, con el fin de mejorar alguna de sus propiedades mecánicas, y al mismo tiempo, dar salida a estos excedentes que causan los neumáticos ya uti-lizados. Con este propósito, el artículo analiza las pro-piedades mecánicas de siete polímeros termoplásticos comunes, los cuales mezclados con el GTR en varios porcentajes y tamaños de partícula de GTR, podrían ser de utilidad en los procesos industriales. De los re-sultados obtenidos, se deduce que esta propuesta es válida, al menos con algunos de tamaños de partícula y porcentajes de GTR analizados.Peer ReviewedPostprint (published version

Anàlisi comparativa de propietats termo estructurals i elèctriques entre el polietilè d'alta densitat (HD-PE) i l’HD-PE reforçat amb pneumàtics al final de la seva vida útil. Estudi d'aplicació com a dielèctric

El propósito del presente trabajo pasa por analizar la permitividad y el factor de pérdidas tanto del polietile-no de alta densidad (HD-PE), como del compuesto de matriz polimérica (HD-PE)reforzado con neumáticos fuera de uso (Ground Tire Rubber: GTR), con el fin de demostrar su viabilidad como material aislante eléc-trico (dieléctrico). Como es sabido, la incorporación de negro de humo en un polímero permite modificar su conductividad, y cómo el GTR lleva un porcentaje significativo de negro de humo, algunas de las pro-piedades eléctricas del nuevo compuesto cambiaran significativamente con respecto al polímero que es altamente aislante. El estudio se centrará, en un rango de frecuencias y temperaturas aptas para demostrar la viabilidad de este nuevo compuesto en usos indus-triales, enfocándolo principalmente en el análisis de la Permitividad, ya que es una propiedad clave para los condensadores. No obstante, también se caracterizará el comportamiento térmico y estructural, haciendo especial énfasis en el rango de trabajo del condensador (por debajo de los 100ºC). Finalmente, con el análisis estructural, se pretende contribuir al conocimiento de estos materiales compuestos provenientes de reciclaje, y así, aprovechar su potencial de reutilización, haciéndolos atractivos para las empresas interesadas en su relación rendimiento/precio.The purpose of this work is to analyze the permittivity and the loss factor of both high-density polyethylene (HD-PE), as well as the polymer matrix composite (HD-PE) reinforced with end-of-life tires (Ground Tire Rubber: GTR), in order to demonstrate its viability as electrical insulating material (dielectric). As is known, the incorporation of carbon black in a polymer allows its conductivity to be modified, and since the GTR carries a significant percentage of carbon black, some of the electrical properties of the new compound will change significantly with respect to the polymer that is highly insulating. The study will focus on a range of frequencies and temperatures suitable to demonstrate the viability of this new composite in industrial uses, focusing mainly on the analysis of Permitivity, since it is a key property for capacitors. However, the thermal and structural behavior will also be characterized, with special emphasis on the capacitor working range (below 100ºC). Finally, with the structural analysis, it is inten-ded to contribute to the knowledge of these composite materials from recycling, and thus, take advantage of their potential for reuse, making them attractive for companies interested in their performance/price ratio.El propòsit del present treball passa per analitzar la permitivitat i el factor de pèrdues tant del polietilè d'alta densitat (HD-PE), com del compost de matriu polimèrica (HD-PE) reforçat amb pneumàtics fora d'ús (Ground Tire Rubber: GTR ), amb la finalitat de demostrar la seva viabilitat com a material aïllant elèctric (dielèctric). Com és sabut, la incorporació de negre de fum en un polímer permet modificar la seva conductivitat, i com el GTR porta un percentatge sig-nificatiu de negre de fum, algunes de les propietats elèctriques del nou compost canvien significativament respecte del polímer, que és altament aïllant. L'estudi es centrarà, en un rang de freqüències i temperatures aptes per demostrar la viabilitat d'aquest nou compost en usos industrials, enfocant principalment en l'anàlisi de la Permitivitat, ja que és una propietat clau per als condensadors. No obstant això, també es caracteritzarà el comportament tèrmic i estructural, fent especial èmfasi en el rang de treball d’un condensador (per sota dels 100 º C). Finalment, amb l'anàlisi estructural, es pretén contribuir a el coneixement d'aquests materials compostos provinents de reciclatge, i així, aprofitar el seu potencial de reutilització, fent-los atractius per a les empreses interessades en la seva relació rendiment/preu.Peer ReviewedPostprint (published version

Endocardial infarct scar recognition by myocardial electrical impedance is not influenced by changes in cardiac activation sequence

Peer ReviewedPostprint (published version