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The utilisation of thermoelectric technology as a heat pump in heating applications necessitates comprehensive investigation. The scalable nature of thermoelectric technology enables its operation at elevated temperatures without the requirement of refrigerants. In this work, an accurate computational model that can simulate one- and two-stage thermoelectric heat pumps is developed. This model uses the electric-thermal analogy and the finite difference method, including the thermoelectric effects, temperature dependent properties, thermal contact resistances and all heat exchangers, even the intermediate heat exchanger in the case of a two-stage configuration. Moreover, the model has been experimentally validated by built and tested prototypes, being the first time that a two-stage thermoelectric heat pump model is experimentally validated. The discrepancy between the simulated and experimental results is below the ± 10 % for , ± 8 % for generated heat and temperature lift in the airflow, and less than the ± 6 % for consumed power. Additonally, the model simulates real tendencies under different operating conditions, proving the reliability of the developed thermoelectric heat pump model. Finally, the model is used to optimise a thermoelectric system combining one- and two-stage thermoelectric heat pumps, and hybridising them with electric resistances. An airflow of 16.5 m3/h is heated from 25 °C to 160 °C, achieving a maximum of 1.21. Lastly, the importance of considering the thermal resistances of the heat exchangers is computationally modelled and demonstrated. Not taking them into account would overestimate the performance of the TEHP system by more than the 7 %. The authors would like to acknowledge the support of the grant TED2021-130071A-I00 funded by MCIN/AEI/10.13039/501100011033 and, as appropriate, by 'European Union Next Generation EU/PRTR', as well as the Government of Navarre, as part of the 'Grants to SINAI agents for the realization of collaborative R&D projects' under the PC066-067-068 FlexORCStorage. Open access funding provided by Universidad Pública de Navarra.

La llegada de las nuevas tecnologías y su aplicación en la ingeniería civil, ha permitido una mirada más transversal de sus aplicaciones; es por ello que, en el siguiente ensayo se propone un novedoso sistema flotante fotovoltaico con el fin de suministrar energía eléctrica en el alto Baudó, el cual permite aprovechar la energía solar y así poder llevar el servicio de energía a la población, esta tecnología en el poco tiempo que lleva de aplicación ha demostrado ser una de las soluciones más amigables y efectivas, al mismo tiempo suministrar los servicios básicos a la comunidad. ; The arrival of new technologies and their application in civil engineering has allowed a more transversal view of their applications; That is why, in the following essay, a novel photovoltaic floating system is proposed in order to supply electrical energy in the upper Baudó, which allows taking advantage of solar energy and thus being able to bring the energy service to the population, this technology in the short time it has been in place has proven to be one of the friendliest and most effective solutions, at the same time providing basic services to the community ; Pregrado

[ES]Se ha elaborado una nueva base de datos de precipitaciones medias mensuales y temperaturas máximas y mínimas medias mensuales, con la que se han analizado los datos de 142 estaciones meteorológicas obtenidos de la Agencia Estatal de Meteorología (AEMET) para el periodo (1989-2018). En este estudio se presentan los resultados de diferentes pruebas de homogeneización y relleno de 134, 172 y 176 series de temperaturas y precipitaciones provenientes de las estaciones ubicadas en la región de Extremadura. Para ello, se realizó un primer control de calidad de los datos cumpliendo con los requisitos de la Organización Meteorológica Mundial (OMM) y las recomendaciones indicadas por el Real Instituto Meteorológico de los Países Bajos (KNMI). Posteriormente se llevó a cabo la homogeneización de las series utilizando el software Climatol, en el que se han implementado diferentes funciones que permiten depurar los datos a través de un análisis de los valores atípicos y de la homogeneidad, así como la completación de las lagunas de las series. Los análisis confirman la obtención de unos niveles de depuración de los datos muy altos, confiables y de buena calidad; obteniendo así una nueva base de datos para posteriores estudios climáticos. [EN]A new database of monthly average rainfall and monthly average maximum and minimum temperatures has been developed, with which data from 142 weather stations obtained from the Agencia Estatal de Meteorología (AEMET) for the period (1989-2018) have been analysed. This study presents the results of different homogenisation and backfilling tests of 134, 172 and 176 temperature and precipitation series from stations located in the region of Extremadura. For this purpose, a first quality control of the data was carried out in compliance with the requirements of the World Meteorological Organisation (WMO) and the recommendations indicated by the Royal Netherlands Meteorological Institute (KNMI). Subsequently, the series were homogenised using Climatol software, in which different functions have been implemented to clean the data through an analysis of outliers and homogeneity, as well as filling in the gaps in the series. The analyses confirm the achievement of very high, reliable and good quality data cleaning levels, thus obtaining a new database for further climate studies. Esta investigación fue financiada por la Junta de Extremadura y el Fondo Europeo de Desarrollo Regional (FEDER) a través de la ayuda al grupo de investigación Alcántara (TIC008), GR21006, y el Proyecto IB18001 “Análisis y modelización del impacto del cambio climático sobre la distribución de zonas vitícolas en Extremadura”. Ponencia presentada en: XII Congreso de la Asociación Española de Climatología celebrado en Santiago de Compostela entre el 19 y el 21 de octubre de 2022.

Flare stacks are a key element in the safety of petrochemical and refinery industries; the correct operating conditions thereof must be ensured through a schedule for the periodic reviewing of all parts thereof. Advances in Non-Destructive Testing (NDT) in recent years and the application thereof to this field allow reliable, objective information to be obtained. This article describes and groups together the main applicable NDT techniques, analysing their advantages and disadvantages, updated with the new possibilities offered by unmanned aircraft or drones.

This work evaluates, for the first time, the possibility of producing multifunctional alkali-activated composites combining ultra-low density, low thermal conductivity, high acoustic absorption, and good moisture buffering capacity. The composites were prepared using cork as a lightweight aggregate. This novel material might promote energy savings and tackle the CO2 emissions of the building sector, while simultaneously improve the comfort for inhabitants (e.g. humidity levels regulation and sound pollution reduction). The composites apparent density (as low as 168 kg/m3) and thermal conductivity (as low as 68 mW/m K) are amongst the lowest ever reported for alkali-activated materials (AAM) composites and foams, while their sound absorption ability is comparable to the best performing AAM foams reported to date, but in addition these eco-friendly composites also show good ability to passively adjust the humidity levels inside buildings. The multifunctional properties shown by the cork – AAM composites set them apart from other conventional building materials and might contribute to the global sustainability of the construction sector. Peer Reviewed

AbstractLightning is the main precursor of natural wildfires and Long-Continuing-Current (LCC) lightning flashes are proposed to be the main igniters of lightning-ignited wildfires (LIW). Previous studies predict a change of the global occurrence rate and spatial pattern of total lightning. Nevertheless, the sensitivity of lightning-ignited wildfire occurrence to climate change is uncertain. Here, we investigate space-based measurements of LCC lightning associated with lightning ignitions and present LCC lightning projections under the Representative Concentration Pathway RCP6.0 for the 2090s by applying a recent LCC lightning parameterization based on the updraft strength in thunderstorms. We find a 41% global increase of the LCC lightning flash rate. Increases are largest in South America, the western coast of North America, Central America, Australia, Southern and Eastern Asia, and Europe, while only regional variations are found in northern polar forests, where fire risk can affect permafrost soil carbon release. These results show that lightning schemes including LCC lightning are needed to project the occurrence of lightning-ignited wildfires under climate change.

Abstract The impact of CO 2 leakage from underground storage formations on shallow water resources is a concerning aspect in CO 2 capture and storage (CCS) risk assessment. In Campo de Calatrava region (Spain), natural CO 2 fluxes from the Earth’s mantle interact with shallow aquifers, resulting in significant changes in their physical and chemical properties. The resultant water is slightly acidic (pH 5.9-6.4), oxidizing, and enriched in iron (up to 6.1×10 -4 mol·L -1 ) and other metals usually found at trace concentrations. Thermodynamic calculations reveal that aqueous Fe(III) carbonate complexes play an important role in the persistence of this high concentration of iron and trace metals in solution.