Efficient and Suitable Construction

This chapter is devoted to study the melting process of a phase change material into a triplex tube heat exchanger with finned copper tubes. The focus is on the heat transfer between a heating fluid (water) and phase change material to power a liquid-desiccant air conditioning system. Here, different topics related to fundamentals and applications of the phase change materials, and storage energy system with especial reference to a triplex tube heat exchanger are presented and discussed. Results of the temperature fields, liquid fraction, and velocity, as well as the energy history of the involved phases in the heating and melting processes are presented, compared with experimental data, and analyzed.

Regardless of the construction processes or employed materials, the NBR 15575 (2013) defines objectives, requirements and methods for assessing the behaviour in use performance of accommodations. Therefore, the influence of the coating layers on the performance of construction systems is an essential parameter to assess the use of materials and elements of the systems, in order to make the project feasible, not only economically, but also technically. Through numerical simulations based on a defined reference model for the study, the present work study the influence of different layers of floor, roof and, internal and external wall systems, on the acoustic performance. Finally, analysing the results, for the reference model used, identified the materials and elements with the greatest influence on acoustic performance of the façade—function especially of the external windows; acoustic performance of the floor system—mainly influenced by the thickness of the structural element and the use of ceiling and acoustic blanket; acoustic performance of internal walls—typology of the structured element of the wall and thickness.

This work presents an extensive numerical simulation to analyse the influence of the coating layers on the performance of construction systems, in order to make the constructions projects feasible, not only economically, but also technically. Through computer simulations based on a defined reference model for the study, the present work study the influence of different layers of floor, roof and internal and external wall systems, on the thermal performance. Finally, analysing the results, for the reference model used, identified the materials and elements with the greatest influence on a thermal - all elements of tension, roofing system and facades, especially an absence of external cladding and the use of thermal blankets on the roof.

The influence of the coating layers on the performance of construction systems is an essential parameter to assess the use of materials and elements of the systems, in order to make the project feasible, not only economically, but also technically. Through numerical simulations based on a defined reference model for the study, the present work study the influence of different layers of floor, roof and, internal and external wall systems, on the natural lighting performance. Finally, analysing the results, for the reference model used, identified the materials and elements with the greatest influence on lighting performance—the internal finishes of the environment and the type of glass used in the external walls.

In determining the temperature field generated within a room subjected to exterior daily variation of temperatures and solar radiation, and in view of the difficulty (or even impossibility) of obtaining analytical solutions for the descriptive differential equations of the phenomenon in most practical applications, numerical tools are used. The choice of the Finite Element Method (FEM) as a numerical methodology for solving the thermal problem associated with heat transfer in current building materials and phase change materials makes sense, as it is a well-known technique, generalize and dominated, however, still little applied to the domain of building physics. The proposed numerical simulation was performed with three main objectives: (i) the numerical resolution of the mathematical problem of heat transfer in phase change materials using the finite element method, in a three-dimensional (3D) analysis; (ii) the validation of numerical simulation capability by comparing the results obtained experimentally with the results obtained numerically; (iii) the evaluation of some of the potentialities of the numerical tool in the treatment and presentation of results. During the experimental campaign two test cells with distinct inner layers: (i) one with a reference mortar, hereinafter referred to as REFM test cell (Without PCM); (ii) another with a PCM mortar, hereinafter referred to as the PCMM test cell (With PCM). The test cells were placed outdoors and therefore have a differential effect of solar radiation. The temperatures monitored inside the REFM and PCMM test cells during the experimental campaign were compared with the values resulting from the numerical simulation using the finite element method with 3D discretization, and the obtained results revealed a significant coherence of values. An application of a solar radiation method was developed and linked, without neglecting the observation of the effect of the PCM.