Field measurement and simulation of a novel passive solar and shallow-geothermal heating system designed for temporary prefabricated houses

Abstract

Temporary buildings have become the main options in emergency situations. However, they usually have poor indoor thermal environment and air quality in winter. In this paper, a novel passive ventilation and heating system utilizing solar and shallow-geothermal for temporary prefabricated houses is proposed. The aims of this study was to experimentally and numerically evaluate the heating performance of the proposed system under cold weather conditions. The field measurement results validated that the passive heating system can provide 24-h ventilation, and effectively elevate the indoor temperature. The average indoor temperature was elevated by 5.3 °C, and the maximum temperature rise was 8.3 °C at night. Simulation results revealed that increasing chimney height can reduce the reverse buoyancy force. The peak ventilation rate increased from 120.2 to 365.7 m³/h, and the indoor temperature increased from 7.2 to 13.1 °C when the chimney height increased from 2 to 5 m. The effects of pipe and ground solar collector lengths on the system performance were not as important as that of the chimney height. The peak daytime airflow rate and indoor temperature increased from 0 to 171.5 m³/h, and from 8.2 to 11.7 °C, respectively, when roof solar collector length increased from 3.6 to 6.0 m.