Avaliação experimental de compósitos de agregados leves impregnados com PCM, para aplicação em pavimentos rodoviários

Este trabalho visa, em primeiro lugar, a caracterização experimental do comportam ento de argamassas com materiais de mudança de fase (PCM) incorporados através de agregados leves, comparativamente com argamassas de referência sem incorporação de PCM. Verifica-se que a aplicação de argamassas com PCM em camadas de desgaste de pavimentos contribui para a minimização dos potenciais efeitos negativos de gelo e degelo. Os estudos experimentais permitem concluir que o método utilizado de impregnação de PCM em materiais porosos, para posterior incorporação em argamassa ou betão, é um método simples, mas muito eficaz. Os resultados indicam ainda que os materiais compósitos com PCM incorporado, podem melhorar a inércia térmica, bem como, atrasar o tempo de eventual ocorrência de congelamento sob a camada de desgaste de um pavimento

Mortars with incorporation of PCM based in different binders: mechanical and thermal behavior

Currently we are witnessing a huge concern of society with the parameters of comfort of the buildings and the energetic consumptions. It is known that there is a huge consumption of non-renewable sources of energy. Thus, it is urgent to develop and explore ways to take advantage of renewable sources of energy by improving the energy efficiency of buildings. The mortars with incorporation of phase change materials (PCM) have the ability to regulate the temperature inside buildings, contributing to the thermal comfort and reduction of the use of heating and cooling equipment, using only the energy supplied by the sun. However, the incorporation of phase change materials in mortars modifies its characteristics. The main purpose of this study was mechanical and thermal characterization of mortars with incorporation of PCM in mortars based in different binders. The binders studied were aerial lime, hydraulic lime, gypsum and cement. For each type of binder a reference composition (0% PCM) and a composition with incorporation of 40% of PCM were developed. It was possible to observe that the incorporation of PCM in mortars caused differences in properties such as workability, compressive strength, flexural strength and adhesion, however leads to an improvement of thermal behavior.

Experimental and numerical studies of hybrid PCM embedded in plastering mortar for enhanced thermal behaviour of buildings

This paper proposes a methodology for improvement of energy efficiency in buildings through the innovative simultaneous incorporation of three distinct phase change materials (here termed as hybrid PCM) in plastering mortars for façade walls. The thermal performance of a hybrid PCM mortar was experimentally evaluated by comparing the behaviour of a prototype test cell (including hybrid PCM plastering mortar) subjected to realistic daily temperature profiles, with the behaviour of a similar prototype test cell, in which no PCM was added. A numerical simulation model was employed (using ANSYS-FLUENT) to validate the capacity of simulating temperature evolution within the prototype containing hybrid PCM, as well as to understand the contribution of hybrid PCM to energy efficiency. Incorporation of hybrid PCM into plastering mortars was found to have the potential to significantly reduce heating/cooling temperature demands for maintaining the interior temperature within comfort levels when compared to normal mortars (without PCM), or even mortars comprising a single type of PCM.

Identificação do tipo e quantidade de PCM adequado ao clima Português

Dissertação de mestrado integrado em Engenharia Civil

Sustainable mortars with incorporation of microencapsulated phase change materials

The construction industry is responsible for high energy and raw materials consumption. Thus, it is important to minimize the high energy consumption by taking advantage of renewable energy sources and reusing industrial waste, decreasing the extraction of natural materials. The mortars with incorporation of phase change materials (PCM) have the ability to regulate the temperature inside buildings, contributing to the thermal comfort and reduction of the use of heating and cooling equipment, using only the energy supplied by the sun. The simultaneous incorporation of PCM and fly ash (FA) can reduce the energy consumption and the amount of materials landfilled. However, the addition of these materials in mortars modifies its characteristics. The main purpose of this study was the production and characterization in the fresh and hardened state of mortars with incorporation of different contents of PCM and FA. The binders studied were aerial lime, hydraulic lime, gypsum and cement. The proportion of PCM studied was 0%, 20%, 40% and 60% of the mass of the sand. The content of fly ash added to the mortars was 0%, 20%, 40% and 60% of the mass of the binder. It was possible to observe that the incorporation of PCM and fly ash in mortars caused differences in properties such as workability, microstructure, water absorption, compressive strength, flexural strength and adhesion.

Optimal behavior of responsive residential demand considering hybrid phase change materials

Due to communication and technology developments, residential consumers are enabled to participate in Demand Response Programs (DRPs), control their consumption and decrease their cost by using Household Energy Management (HEM) systems. On the other hand, capability of energy storage systems to improve the energy efficiency causes that employing Phase Change Materials (PCM) as thermal storage systems to be widely addressed in the building applications. In this paper, an operational model of HEM system considering the incorporation of more than one type of PCM in plastering mortars (hybrid PCM) is proposed not only to minimize the customerâ s cost in different DRPs but also to guaranty the habitantsâ  satisfaction. Moreover, the proposed model ensures the technical and economic limits of batteries and electrical appliances. Different case studies indicate that implementation of hybrid PCM in the buildings can meaningfully affect the operational pattern of HEM systems in different DRPs. The results reveal that the customerâ s electricity cost can be reduced up to 48% by utilizing the proposed model.

Ranking procedure based on mechanical, durability and thermal behavior of mortars with incorporation of phase change materials

Nowadays, considering the high variety of construction products, adequate material selection, based on their properties and function, becomes increasingly important. In this research, a ranking procedure developed by Czarnecki and Lukowski is applied in mortars with incorporation of phase change materials (PCM). The ranking procedure transforms experimental results of properties into one numerical value. The products can be classified according to their individual properties or even an optimized combination of different properties. The main purpose of this study was the ranking of mortars with incorporation of different contents of PCM based in different binders. Aerial lime, hydraulic lime, gypsum and cement were the binders studied. For each binder, three different mortars were developed. Reference mortars, mortars with incorporation of 40% of PCM and mortars with incorporation of 40% of PCM and 1% of fibers, were tested. Results show that the incorporation of PCM in mortars changes their global performance.

Estudo de revestimentos ativos para o isolamento térmico de edifícios

Dissertação de mestrado em Sustentabilidade do Ambiente Construído

Incorporation of hybrid phase change materials in plastering mortars for increased energy efficiency in buildings

Tese de Doutoramento em Engenharia Civil.