Because of poor heat transfer coefficients of soil/rock, ground source heat pumps (GSHP) or underground thermal energy storage (UTES) systems always occupy a large area and need many ground heat exchangers. This initial energy investment is so heavy that it cannot be used on a large-scale....

In this paper a numerical model to analyze the thermal behaviour of vertical ground heat exchangers with a helical shaped pipe is presented. This type of configuration can be a suitable alternative to conventional ground heat exchangers, especially when the heating and cooling loads of the...

When the ground coupled heat pump (GCHP) system is utilized for air conditioning in cooling load dominated buildings, the heat rejected into ground will accumulate around the ground heat exchangers (GHE) and results in system performance degradation. A novel hybrid ground coupled heat pump...

This paper makes a comparative analysis between a helical-shaped pipe and a double U-tube ground heat exchanger. The two configurations were installed at a shallow depth and studied, since a depth limit is mandatory in some areas. When installed this way, the interaction between the ground...

This work analyzes influence of anisotropy of anisotropic soil on the processes of heat transfer by ground heat exchangers used in ground-coupled heat pump systems. First, this paper uses the heat-source theory to develop several explicit exact solutions for heat conduction in anisotropic...

The issue of natural and forced groundwater movements, and its effect on the performance of ground heat exchangers is of great importance for the design and sizing of borehole thermal energy systems (BTESs). In Scandinavia groundwater filled boreholes in hard rock are commonly used. In such...

This paper presents the cooling performance of a water-to-refrigerant type ground heat source heat pump system (GSHP) installed in a school building in Korea. The evaluation of the cooling performance has been conducted under the actual operation of GSHP system in the summer of year 2007. Ten...

The objective of this study is to show the temperature distribution development in the borehole of the ground-coupled heat pump systems (GCHPs) with time. The time interval for the study is 48h. The vertical GCHP system using R-22 as refrigerant has a three single U-tube ground heat exchanger...

In this paper different approaches to groundwater flow and its effect in the vicinity of a borehole ground heat exchanger are discussed. The common assumption that groundwater flow in hard rock may be modelled as a homogeneous flow in a medium with an effective porosity is confronted and models...

A simplified three-dimensional finite difference model for a single (cylindrical energy pile) CEP was developed. The present model was first verified with an analytical solution based on the special case that the material inside and outside the CEP had the same thermal properties. For the case...