Performance analysis of domed roof integrated with earth-to-air heat exchanger system to meet thermal comfort conditions in buildings

Abstract

In the present study, an integrated cooling system consisting an earth-to-air heat exchanger (EAHE) and a domed roof is investigated numerically to meet the thermal comfort conditions and supply the cooling demand for a building. Simulation of airflow in the EAHE and a test room with the domed roof is performed with ANSYS FLUENT software three-dimensionally, and the thermal behavior of the system is modeled with the code developed in MATLAB software. Furthermore, for verifying the numerical results of EAHE modeling, an experimental study is conducted. The impact of both geometric and environmental parameters on the system performance is also investigated. The obtained results reveal that the system is capable of providing thermal comfort conditions, according to adaptive thermal comfort standard (ATCS), for the test room with a maximum cooling demand of about 1000 W alone and without consuming electric energy by using three pipes with a length of 35 m and a diameter of 0.4 m. The application of the proposed system instead of the split inverter air conditioner and the evaporative cooler to provide a similar cooling load can reduce the electrical energy consumption up to 0.360 kW h, and 0.200 kW h, respectively. In addition, the environmental analysis indicates that the utilization of this system instead of the split inverter air conditioner and evaporative air cooler with similar capacities leads to respective 361.89 kg and 216.06 kg reduction in CO2 emissions for summer months. Finally, the application of the proposed integrated system for a two-story building with domed roof is evaluated. The results show the ability of the system to provide thermal comfort for the two-story building with a maximum cooling demand of approximately 300 W for each floor using two pipes with a length of 35 m and a diameter of 0.4 m.