Análisis comparativo de cápsulas plásticas para uso material de cambio de fase en un entorno de materiales livianos.
Loading...
Date
2025
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Universidad de Concepción
Abstract
La climatización de edificaciones livianas y su baja inercia térmica representan un desafío para la eficiencia energética. En este contexto, los materiales de cambio de fase (PCM) han surgido como una alternativa para mejorar la regulación térmica natural, permitiendo almacenar y liberar energía en forma de calor latente. Sin embargo, su desempeño térmico depende de la forma de encapsulación y la interacción con los elementos de la aplicación en que se ocupe. Este estudio analiza el impacto de la forma y orientación de cápsulas plásticas de PCM en la estabilidad térmica de un sistema de materiales livianos, evaluando tres tipos de encapsulación (simple, tubos y cuadros) fabricadas con PVC y wax de parafina como PCM. Se realizaron ensayos experimentales en un banco de pruebas compuesto por cubos instrumentados con sensores de temperatura, expuestos a condiciones ambientales en dos configuraciones: vertical, ubicando las cápsulas en una posición similar al de estar inmersos en una pared, y horizontal, donde las cápsulas están instaladas como cielo falso de una construcción.
Los resultados indican que la geometría del encapsulado influye significativamente en la regulación térmica del aire interior. En la configuración vertical, la cápsula Cuadros mostró una reducción de hasta 22.81% en la amplitud térmica diaria, atribuida a la compartimentación del PCM, que minimiza la convección interna y mejora la estabilidad térmica. Sin embargo, la cápsula Tubos, pese a tener compartimentos más pequeños, presentó un menor desempeño debido a la mayor cantidad de juntas internas, las cuales generan puentes térmicos que pueden dificultar la transferencia de calor dentro del encapsulado. En la configuración horizontal, donde la gravedad tiene menor influencia en la redistribución del PCM, las diferencias entre diseños fueron menos pronunciadas, con un desempeño levemente superior del diseño simple, debido a la ausencia de estos puentes térmicos. Además, se observó el fenómeno de subenfriamiento en la solidificación del PCM, donde el material permaneció en estado líquido por debajo de su temperatura de fusión antes de cristalizar, lo que afecta la eficiencia del almacenamiento térmico.
Estos hallazgos aportan al diseño de estrategias de encapsulación optimizadas para PCM en construcción liviana, evidenciando que la compartimentación mejora la estabilidad térmica en ciertas orientaciones, pero una reducción excesiva del tamaño de los compartimentos puede aumentar la resistencia térmica. Como trabajo futuro, se propone optimizar la geometría del encapsulado, evaluar su desempeño en diversas condiciones climáticas e investigar la viabilidad comercial de esta tecnología como solución sostenible para la eficiencia energética en edificaciones.
The increasing energy demand of lightweight buildings and their low thermal inertia pose a challenge for energy efficiency. In this context, phase change materials (PCM) have emerged as an alternative to enhance thermal regulation by storing and releasing heat through phase transitions. However, their thermal performance depends on the encapsulation design and its interaction with the building envelope. This study analyzes the impact of the shape and orientation of plastic PCM capsules on the thermal stability of a lightweight construction system, evaluating three types of encapsulations (simple, tubes, and squares) made of PVC with paraffin wax as the PCM. Experimental tests were conducted using test cubes equipped with temperature sensors, exposed to environmental conditions in two configurations: vertical and horizontal. The results indicate that the geometry of encapsulation significantly influences indoor thermal regulation. In the vertical configuration, the squares capsule reduced daily thermal amplitude by up to 22.81%, attributed to the PCM compartmentalization, which minimizes internal convection and improves thermal stability. However, the Tubes capsule, despite having smaller compartments, exhibited lower performance due to the higher number of internal joints, which create thermal bridges that can hinder heat transfer within the encapsulation. In the horizontal configuration, where gravity has less influence on PCM redistribution, the differences between designs were less pronounced, with the simple design performing slightly better due to the absence of these thermal bridges. Additionally, supercooling during PCM solidification was observed, where the material remained in a liquid state below its melting temperature before crystallizing, affecting thermal storage efficiency. These findings contribute to the design of optimized PCM encapsulation strategies for lightweight construction, demonstrating that compartmentalization enhances thermal stability in certain orientations, but excessive reduction in compartment size can increase the number of thermal bridges, impacting system efficiency. Future work should focus on optimizing the encapsulation geometry, assessing its performance in varied climatic conditions, and investigating the commercial feasibility of this technology as a sustainable solution for energy-efficient buildings.
The increasing energy demand of lightweight buildings and their low thermal inertia pose a challenge for energy efficiency. In this context, phase change materials (PCM) have emerged as an alternative to enhance thermal regulation by storing and releasing heat through phase transitions. However, their thermal performance depends on the encapsulation design and its interaction with the building envelope. This study analyzes the impact of the shape and orientation of plastic PCM capsules on the thermal stability of a lightweight construction system, evaluating three types of encapsulations (simple, tubes, and squares) made of PVC with paraffin wax as the PCM. Experimental tests were conducted using test cubes equipped with temperature sensors, exposed to environmental conditions in two configurations: vertical and horizontal. The results indicate that the geometry of encapsulation significantly influences indoor thermal regulation. In the vertical configuration, the squares capsule reduced daily thermal amplitude by up to 22.81%, attributed to the PCM compartmentalization, which minimizes internal convection and improves thermal stability. However, the Tubes capsule, despite having smaller compartments, exhibited lower performance due to the higher number of internal joints, which create thermal bridges that can hinder heat transfer within the encapsulation. In the horizontal configuration, where gravity has less influence on PCM redistribution, the differences between designs were less pronounced, with the simple design performing slightly better due to the absence of these thermal bridges. Additionally, supercooling during PCM solidification was observed, where the material remained in a liquid state below its melting temperature before crystallizing, affecting thermal storage efficiency. These findings contribute to the design of optimized PCM encapsulation strategies for lightweight construction, demonstrating that compartmentalization enhances thermal stability in certain orientations, but excessive reduction in compartment size can increase the number of thermal bridges, impacting system efficiency. Future work should focus on optimizing the encapsulation geometry, assessing its performance in varied climatic conditions, and investigating the commercial feasibility of this technology as a sustainable solution for energy-efficient buildings.
Description
Tesis presentada para optar al título de Ingeniero Civil Mecánico
Keywords
Plasticos Diseño, Eficiencia térmica, Materiales de construcción