Analysis and design of a drain water heat recovery storage unit based on PCM plates

© 2016. This version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/This paper is focused on the detailed analysis of a PCM plate heat storage unit with a particular configuration, looking for the maximum contact area with the fluid (water) and the minimum volume to be used in a real household application. In that sense, a numerical study of the thermal and fluid dynamic behaviour of the water flow and the PCM melting-solidification processes, together with the thermal behaviour of the solid elements of the unit, has been carried out. On the other hand, an experimental set-up has been designed and built to validate the numerical model and characterise the performance of the heat storage unit. The purpose of the numerical and experimental study is to present a series of results to describe the heat storage unit performance in function of the time. Thus, after a preliminary design study three different cases have been simulated and tested. A 7.2% of discrepancy between numerical results and experimental data has been evaluated for the heat transfer. The PCM heat storage unit designed is capable to store approx. 75% of the thermal energy from the previous process wasted water heat, and recover part of it to supply around 50% of the thermal energy required to heat up the next process.Peer ReviewedPostprint (author's final draft

Minimization procedure of experimental tests for calibration purposes, within HVAC&R energy efficiency framework

Simulation models and predictive tools need to be fast, accurate and robust at the same time. The models that have to provide numerical solutions under transient conditions for a long period of time need to be simple with the aim of minimizing the time respond, without losing the accuracy. Thus, previous experimental data and a calibration methodology are necessary to assure this objective, both are strictly necessary to reproduce the behaviour with accuracy expected. Consequently, even accurate information (e.g. look-up tables) for HVAC&R components (e.g. heat exchangers, fan/compressor, auxiliary elements, etc.) is known and all coupling system is developed, the minimization of experimental tests for calibration purposed based scattered data interpolation is now an important aspect, which looks for reducing the quantity of experiments necessary to assure the accuracy expected from an optimization point of view. The present work shows an optimization procedure based on test number minimization according detailed error comparison against existing previous data. Illustrative results for a specific component are presented highlighting test number reduction without losing accuracy.This project has received funding from the Clean Sky 2 Joint Undertaking under the European Union’s Horizon 2020 research and innovation programme under grant agreement No 755517.Peer ReviewedPostprint (published version

Distrofia neuroaxonal en el Rottweiler : caso clínico y revisión bibliográfica en el perro y el gato

Se describe el caso clínico de un Rottweiler adulto con distrofia neuroaxonal, sospechada clínicamente y confirmada mediante el estudio histopatológico (implica la presencia microscópica de dilataciones axonales). En este caso se trata de una enfermedad neurodegenerativa de carácter crónico progresivo, y con desenlace fatal. El diagnóstico presuntivo se establece en base al cuadro clínico y tras la exclusión de otras enfermedades mediante las pruebas complementarias. La distrofia neuroaxonal se presenta con mayor frecuencia en el Rottweiler que en otras razas, aunque con relativa variabilidad en el cuadro clínico

Supervivencia de datos y resistencia a fallos en redes multiservicio con software open source

The goal in this project is to design multifunction server, reliable and safe. Two different topics will be described, one of them related on corporation field and the other one related with home. This project describes both scenarios, the corporative one's implements a data security system where information would be secure using physical protection or software protection. The one focused on home, ease the user access to get multimedia content and protect data using similar mechanism of corporation one. In the introduction , reader will be introduce in a bunch of problems and how and why FreeNAS it's the tool chosen to get issue solved. In used technologies, it is explained the many technologies that would be applied in both scenarios .This it is presented to the reader to avoid missing some important concept. In chapter 4 and 5 the scenarios would be described and would be exposed how FreeNAS would offer many appliance. The project would be concluded explaining which possible appliances would be able to be implemented using FreeNAS Tool and forecasting implementations In the annexes, explanations would get in to deeper understanding to avoid hinder the and try to provide more details. This project has been designed, implemented and thought by Carles Artigas Morales FreeNAS offers as well hundreds of new possibilities that couldn't been implemented in this project due the hugeness of possibilities that FreeNAS offers . All possibilities have the same capabilities as the ones implemente

Continuos integration and monitorization system for code quality and cooperation work

Nowadays it exist a sort of tools that allow a greater management of developing projects and although it allows by using this tools increase the efficiency and the effectiveness of the developing process and the developer knowledge. Therefore in this project it will be presented, implemented and tested a set of tool for this purpose. This Project will mainly analyze the code quality and de workers cooperation, in order to do that different software will be used. Sonar will be used as the tool of code analysis which provides a powerful feedback that will be explained in this project. Artifactory will be used to speed up the building time and to save as much bandwidth as possible. Jira will be used as a tracking and cooperation tool and will be fed using sonar feedback. Nagios will monitorize that everything is working as it has and will warn whether a fail happens. Everything will be simulated in scenario trying to get close to reality and giving maximum importance to the cooperation and code quality. Furthermore, the implemented software will be analyzed as wel

Coves de Santa Maira (Castell de Castells, La Marina Alta, Alacant). Campaña de 2008

Resultados de la campaña de excavación de 2008

¿Sueña la juventud vulnerable con trabajos precarios? la toma de decisiones en los itinerarios de (In/Ex)clusión educativa

Este trabajo aborda el análisis de los discursos de jóvenes que han tenido dificultades en su itinerario educativo y que han participado en 'itinerarios de segunda oportunidad'. A partir de entrevistas a jóvenes, pretendemos aproximarnos a los argumentos desde los que dan sentido a sus itinerarios académicos y a las decisiones a las que se han enfrentado. Estos argumentos muestran fuertes implicaciones de la posición social de los actores, y están influidos por agentes de la institución educativa y familiar. En ese marco los jóvenes van configurando unas expectativas de futuro. Estas expectativas se debaten entre tres vías: salidas a espacios laborales poco cualificados y precarios, aunque funcionales al sistema productivo; salidas a entornos protegidos con una elevada dependencia; o salidas a vías marginales que les devuelven a redes de proximidad de alta vulnerabilidad. Estos itinerarios evidencian la tensión entre la reproducción social y la resistencia. This work analyses young people's discourses characterized by problematic educational tracks, and who have been part of "second opportunity itineraries". Based on interviews to the young, we try to understand the arguments they use to make sense of their own academic itineraries and the key decisions they have taken in this process. Their arguments highly relate with the actor's social position, and are influenced by agents such as the family and the educational institution. Within this framework, youngsters construct expectations for the future. These expectations follow three different paths: low-qualified and precarious work arenas, which remain functional in the productive system's context; protected settings with high dependency levels; and marginal paths which takes them to proximity networks with high vulnerability. These tracks show the tension between social reproduction and resistance

Traumatic L7 articular processes fracture and spondylolisthesis following dorsal lumbosacral laminectomy in a cat

Case summary A 12-year-old neutered male domestic shorthair cat was presented to our referral hospital with a chronic history of tenesmus and lumbosacral pain. A diagnosis of degenerative lumbosacral stenosis (DLSS) was made and a standard dorsal L7–S1 laminectomy was performed uneventfully, with complete recovery within 1 month. The cat was brought back 4 months later for investigation of lumbosacral pain after having suffered a minor traumatic event. Neurological examination identified a low tail carriage, weakness, exercise intolerance, left pelvic limb lameness and diminished withdrawal reflexes in both pelvic limbs with severe sacrocaudal pain. A traumatic facet fracture of the L7 articular processes and subsequent spondylolisthesis was diagnosed. A second surgery was performed to stabilise the region. The cat was normal on neurological examination 1 month later and no further clinical signs were noted. Relevance and novel information This is the first description of a fracture and spondylolisthesis as a possible postoperative complication after L7–S1 dorsal laminectomy in a cat. The case highlights the importance of postoperative changes in the supportive structures of the lumbosacral spine in cats after surgical treatment of DLSS

Dynamic Performance of a Mechanical Vapor Compression (MVC) Desalination System

This paper presents a numerical model to analyze the thermal and fluid dynamic behavior of a mechanical vapour compression MVC desalination system. The MVC desalination method is an evaporation and condensation process that occurs at low pressure, which requires a compression work to increase the saturation temperature of the vapor. The compressed vapor is condensed and its latent heat is transferred to the feed seawater. The MVC desalination is used at low and medium scale in comparison with other techniques such as: multistage flash desalination (MSF) or reverse osmosis (RO). The MVC desalination unit studied in this paper uses renewable energy to supply the electricity required by the different devices that make up the unit. The reason to use renewable energy is that the MVC desalination system has been though to work in remote places, where an electric grid is not available. However, using renewable energy means variability in the supply power. This variability should be well defined to avoid damage and establish secure partial working operation of the MVC desalination system. The transient and steady-state behaviors of the desalination system are evaluated taking into account the variability of the renewable energy sources (solar and wind energy). The MVC desalination system has been divided in three different subsystems, following the strategy proposed by Mazini (2014). The first subsystem is the evaporator and condenser, in which the evaporation and distillation processes are performed. The second is the vacuum and deareation subsystem, where the low pressure is achieved and non-condensed gas (Oxygen) is stripped. The last subsystem is the mechanical compressor, which is modeled to know its energetic requirement in function of the desalination performance and the climatic conditions. The mathematical formulation of the evaporator/condenser and vacuum subsystem is based on mass, energy and salt balance conservation equations. Whilst the compressor model is based on the root blower laws, in which the volumetric flow, velocity, power and the displacement by revolution values are related. The group of equations is solved by means of the in-house object-oriented tool called NEST, which is capable to link and solve different elements that making up a system (Damle, et. al., 2011). The MVC desalination system that is presented in this paper has different components: an evaporator/condenser, a compressor, a deareator, two heat exchangers and a group of pumps. Although in this numerical platform each component is an object, the whole system resolution is carried out iteratively for solving all its components and transferring the appropriated information between them. A scalability study has been carried out to find the relation between the variability of the renewable energy sources and the capacity of the desalination system (distilled water production). The influence of the feed seawater conditions is also analyzed on the system performance

Geological setting and genesis of stratabound barite deposits at Múzquiz, Coahuila in northeastern Mexico

Peer ReviewedPreprin