Effect of the distance between the pipes on the thermal performance of multi-pipe earth-to-air heat exchangers with parallel pipes

Document Type : Mechanics article


1 Faculty of Mechanical Engineering, University of Tabriz, Tabriz, Iran

2 Islamic Azad Univ., Ahar branch, Ahar, Iran

3 Assistant professor, Department of Mechanical Engineering, University of Mohaghegh Ardabili, Ardabil, Iran


In this research, the thermal performance of the earth -to-air exchanger with three parallel pipes is simulated in 3D. The thermal saturation of the soil in the considered exchanger with a length of 30 m and a burial depth of 3 m in Tehran city has been investigated. The aim of the research is to investigate the effect of the distance between the pipes on the thermal saturation of the around soil consequently, its effect on the exit temperature and the overall heat transfer rate. The results showed that in the first days of operation, the temperature of the air exiting from the middle and side pipes does not change much; But with the passage of time, the temperature of the air in the middle pipe decreases to a smaller amount than the side pipes. The distance between the pipes has a significant effect on the outlet temperature of the middle and side pipes, especially after a few days of system operation. By increasing the distance between the pipes from 25 to 50, 75 and 100 cm, the heat transfer amount from the middle pipe at a flow rate of 0.1 kg/s increases by 14.5%, 26.5 and 35.6%, respectively.


Main Subjects

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