The performance simulation of the borehole heat exchanger of a ground source heat pump embedded in the building concrete pile

Document Type : Original Article

Authors

1 Assistant Professor, Research Institute for Development and Optimization of Energy Technologies, Research Institute of Petroleum Industry, Tehran, Iran

2 MSc, Department of Mechanical Engineering, West Tehran Branch of Islamic Azad University, Tehran, Iran

3 MSc, School of Mechanical Engineering, Faculty of Engineering, University of Tehran, Tehran, Iran

Abstract

Ground Source Heat Pump (GSHP) systems are growing technologies that are widely used to collect energy for different uses. This widely usage can be due to their high efficiency, considerable energy storage potential, and low operating cost. In this paper, a ground source heat pump, which its ground heat exchanger is embedded in the building concrete pile, is going to be analyzed. Building piles, also known as energy piles, reduce the cost of drilling boreholes. In this study, Computational Fluid Dynamics (CFD) is used to evaluate and understand how energy piles work and the effects of some parameters such as thermal conductivity coefficient of the pile, pile diameter, pipe diameter and pile loops are investigated by using it. The results show that the increase of each of these parameters results in rising GSHP efficiency. Furthermore, increasing the number of the pile loops can affect the pressure drop and the power needed for fluid flow. The results of this work can be used for designing or optimizing the performance of the GSHP systems with the ground heat exchanger embedded in the building concrete pile.

Keywords


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