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Browsing Centros UC by browse.metadata.categoriaods "07 Energía asequible y no contaminante"

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    Constructal design of salt-gradient solar pond fields
    (John Wiley & Sons, 2016) González, Daniel I.; Amigo Álvarez, José Manuel; Lorente, Sylvie; Bejan, Adrian; Suárez Poch, Francisco Ignacio; CEDEUS (Chile)
    Salt-gradient solar ponds (SGSPs) are water bodies that capture and accumulate large amounts of solar energy. The design of an SGSP field has never been analyzed in terms of studying the optimal number of solar ponds that must be built to maximize the useful energy that can be collected in the field, or the most convenient way to connect the ponds. In this paper, we use constructal design to find the optimal configuration of an SGSP field. A steady-state thermal model was constructed to estimate the energy collected by each SGSP, and then a complementary model was developed to determine the final temperature of a defined mass flow rate of a fluid that will be heated by heat exchangers connected to the solar ponds. By applying constructal design, four configurations for the SGSP field, with different surface area distribution, were evaluated: series, parallel, mixed series-parallel and tree-shaped configurations. For the study site of this investigation, it was found that the optimal SGSP field consists of 30 solar ponds of increasing surface area connected in series. This SGSP field increases the final temperature of the fluid to be heated in 22.9%, compared to that obtained in a single SGSP. The results of this study show that is possible to use constructal theory to further optimize the heat transfer of an SGSP field. Experimental results of these configurations would be useful in future works to validate the methodology proposed in this study
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    Development and validation of a numerical heat transfer model for PCM glazing: Integration to EnergyPlus for office building energy performance applications
    (Elsevier Ltd, 2024) Uribe, Daniel; Vera, Sergio; Perino, Marco; CEDEUS (Chile)
    © 2024 Elsevier LtdGlazing filled with Phase Change Materials (PCMs) or PCM glazing arises as a strategy to improve the office buildings' energy performance by providing thermal inertia to glazed façades. PCM glazing can reduce office buildings' cooling energy consumption in warm climates. Literature shows a good understanding of PCM glazing thermophysical properties. However, nowadays, it is unfeasible to estimate the energy consumption of offices with PCM glazing based on annual energy simulations. Therefore, this paper aims to integrate a novel, developed, and validated PCM glazing heat transfer model for building energy performance applications into EnergyPlus. In order to do this, a numerical heat transfer model of a double-clear glazed filled with PCM based on literature is developed. This model is validated experimentally and integrated into EnergyPlus, a state-of-the-art building energy simulation tool. Annual simulations are carried out for an office room with different WWR, façade orientations, and PCMs in four climate conditions to show the model's capability to estimate the energy consumption and cooling peak load reductions. The results show that double-clear glazing filled with PCM can reduce the energy consumption of an office building up to 9.1 % and reduce the cooling peak loads up to 10.5 % compared to the same office building with a triple-clear glazing filled with argon. The best results were observed in warm climates with significant diurnal temperature variations.
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    Improvement of the thermal performance of hollow clay bricks for structural masonry walls
    (2024) Vera Araya, Sergio Eduardo; Figueroa Cofré, Camilo Iván; Chubretovic Arnaiz, Soledad; Remesar Lera, José Carlos; Vargas, Felipe; CEDEUS (Chile)
    Although structural masonry walls are widely used in construction, achieving lower U-value is crucial to minimize energy losses and greenhouse gas emissions. The effect on the U-value of hollow clay masonry walls is evaluated by modifying the clay and mortar thermal conductivities, as well as the brick grid and thickness. Heat transfer through bricks and walls was modeled using a 3D-finite element method while model validation was based on experimental tests. Smaller rectangular cavities reduce the U-value to 0.761 W/m2K; increasing the brick thickness reduces the U-value to 0.563 W/m2K. Moreover, reducing the clay thermal conductivity showed negligible reductions in the wall U-value.
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    Local and NON-LOCAL source apportionment of black carbon and combustion generated PM2.5
    (Elsevier Ltd, 2024) Rodríguez Rangel, Jessika Carolina; Villalobos, Ana María; Castro-Molinare J.; Jorquera González, Héctor Iván Joaquin; CEDEUS (Chile)
    Current methods for measuring black carbon aerosol (BC) by optical methods apportion BC to fossil fuel and wood combustion. However, these results are aggregated: local and non-local combustion sources are lumped together. The spatial apportioning of carbonaceous aerosol sources is challenging in remote or suburban areas because non-local sources may be significant. Air quality modeling would require highly accurate emission inventories and unbiased dispersion models to quantify such apportionment. We propose FUSTA (FUzzy SpatioTemporal Apportionment) methodology for analyzing aethalometer results for equivalent black carbon coming from fossil fuel (eBCff) and wood combustion (eBCwb). We applied this methodology to ambient measurements at three suburban sites around Santiago, Chile, in the winter season 2021. FUSTA results showed that local sources contributed ∼80% to eBCff and eBCwb in all sites. By using PM2.5 – eBCff and PM2.5 – eBCwb scatterplots for each fuzzy cluster (or source) found by FUSTA, the estimated lower edge lines showed distinctive slopes in each measurement site. These slopes were larger for non-local sources (aged aerosols) than for local ones (fresh emissions) and were used to apportion combustion PM2.5 in each site. In sites Colina, Melipilla and San Jose de Maipo, fossil fuel combustion contributions to PM2.5 were 26 % (15.9 μg m−3), 22 % (9.9 μg m−3), and 22 % (7.8 μg m−3), respectively. Wood burning contributions to PM2.5 were 22 % (13.4 μg m−3), 19 % (8.9 μg m−3) and 22% (7.3 μg m−3), respectively. This methodology generates a joint source apportionment of eBC and PM2.5, which is consistent with available chemical speciation data for PM2.5 in Santiago.
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    Mapping Energy Poverty: How Much Impact Do Socioeconomic, Urban and Climatic Variables Have at a Territorial Scale?
    (MDPI, 2022) Encinas, Felipe; Truffello, Ricardo; Aguirre-Nunez, Carlos; Puig, Isidro; Vergara-Perucich, Francisco; Freed, Carmen; Rodriguez, Blanca; CEDEUS (Chile)
    Energy poverty, considered a form of deprivation distinct from income poverty, is associated with three factors: low-income levels, high energy costs, and poor residential energy efficiency. It is necessary to study the socio-spatial distribution of energy poverty, particularly in metropolitan areas, due to persistent socioeconomic segregation and their public agenda implications, including the U.N. SDGs. A model of these characteristics can propose a spatial analysis of urban and climate implications, contributing evidence for public policy. This article aims to address energy poverty from a spatial approach extended to the urban area in Santiago de Chile through an exploratory model that estimates the impact of socioeconomic, urban, and climatic variables at a territorial scale on the performance of homes. Using a geographical weighted regression with the inside home temperature in winter as the dependent variable, the independent variables were the percentage of professionals, NDVI, annual thermal amplitude, and housing material quality. A housing quality pattern that acts as a proxy for vulnerability to energy poverty was found, repeating the distribution pattern of the different socioeconomic sectors. The findings incorporate a new interpretive matrix into the complex reproduction of segregation and inequality in a capital city from a developing country.
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    Modelling and Validation of two Heat and Mass Transfer Model of Living Walls and Evaluation of Their Impact on the Energy Performance of a Supermarket in a Semiarid Climate
    (International Building Performance Simulation Association - IBPSA, 2020) Garcia Zulch, Mauricio Alejandro; Vera Araya, Sergio Eduardo; Rouault, Fabien Guillaume Henri Roger; Bustamante Gómez, Waldo; CEDEUS (Chile)
    There are about 35 heat and mass transfer green roof models up to date. However, there are only four living wall models. Furthermore, there are very few studies on the impact of living walls on the building energy performance of buildings. Moreover, none of the living wall models has been validated under semiarid climate conditions and there is a lack of studies about the cooling potential of living walls in retail buildings such as supermarkets. This paper aims to adapt two well-known green roof models to be able to model the heat and mass transfer through living walls, validate both models under semiarid climate conditions, and couple both adapted and validated models to EnergyPlus. Therefore, the impact of living walls on the energy performance of an ASHRAE prototype supermarket located in Santiago of Chile is evaluated. The results show that living walls can reduce up to 24% the cooling loads of a supermarket, and the wall thermal insulation significantly diminishes the impact of the living wall.
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    REVIEW AND COMPARISON OF DIFFERENT TIMBER BUILDING PRODUCTS' EMBODIED EMISSIONS USING FREE DATABASES
    (World Conference on Timber Engineering, 2023) Victorero Castaño, Felipe Andrés; Mendez, Daniela; Bascuñan, Felipe; Bustamante Gómez, Waldo; CEDEUS (Chile)
    This paper aims to present a brief review of sources of information for studying the variability of embodied carbon emissions in structural wood products commonly used in construction. The review considered 13 primary sources, focused on EPDs and generic databases, and allowed the collection of data for the study of 140 products divided into Sawn lumber, Glulam, OSB, and Plywood. The information collected made it possible to identify factors such as the variability of density properties, wood species, the origin of the products, among others. In addition to analyzing the variations in the biogenic carbon of the different products studied. The results allow us to conclude that although the variability of wood products can be significant, like any product of natural origin, when they are studied within the framework of the analysis of the materials of a building, they can present a smaller fluctuation than other materials such as concrete. Moreover, this effect can be accentuated in wood products with greater density or have undergone processes that increase the mass of biogenic carbon per cubic meter in the final product.