Análise de desempenho termoenergético de um sistema de trocadores de calor solo-ar em habitações populares na Zona Bioclimática 2, Pelotas – RS

Abstract

This study evaluates the thermal performance, energy efficiency, and thermal comfort of users in a popular model single-family dwelling following the "Minha Casa Minha Vida" project by CAIXA, located in Pelotas/RS, using computational simulation. The study compares Natural Ventilation systems, air conditioning, and ground-air heat exchangers in the region, with the analysis year set to 2016. The objectives are to analyze residential energy consumption, thermoenvironmental performance, and user thermal comfort. To achieve this, three simulations were conducted for each ventilation system type, totaling four simulations. EnergyPlus version 9.4 and SketchUp were employed for computational thermal performance analysis and housing modeling, respectively. Climate files were developed during the research. Thermal comfort variations in the single-family residence were evaluated and compared, following the national model of the CAIXA housing project, considering the meteorological characteristics of Pelotas and complying with standards NBR 15220 - Thermal Performance of Buildings and NBR 15575 - Performance in Residential Buildings. Thermal comfort was assessed through simulations using the number of hours within comfort conditions in the building, following the adaptive model diagram from ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers). This analysis correlated monthly averages of external temperatures with internal temperature intervals considered comfortable for 80% and 90% of users. The results of the analyses allowed for an evaluation of thermal comfort in the single-family residence, revealing that the Ground-Air Heat Exchanger system provided greater user comfort throughout the year, with 6.3% improvement compared to Natural Ventilation systems, and 4.56% improvement when ducts were integrated with artificial air conditioning.