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...

Ground source heat pump systems are often coupled to the ground by circulating a fluid through vertical Borehole Heat Exchangers (BHEs). The design of a system requires estimates of the ground thermal conductivity and the borehole thermal resistance, which are usually determined by an in situ...

Hybrid ground source heat pump (HGSHP) system coupled with supplemental heat rejection equipment in parallel configuration is suitable for buildings where the cooling load is much higher than the heating load. Appropriate control is expected to improve its energy efficiency. A control strategy...

A modified three-dimensional finite difference model for the borehole ground heat exchangers of a ground-source heat pump (GSHP) system was developed which accounted for multiple ground layers with different thermal properties in the borefield at no groundwater flow. The present model was used...

A conventional thermal response test (TRT) provides a bulk estimate of the subsurface and borehole thermal properties over the length of the ground heat exchanger (GHE). The measurement of temperature inside the borehole during a TRT can be carried out to further determine thermal properties at...

Experimental investigations are performed to determine the viscosity of TiO2 and Al2O3 nanoparticles suspended in a mixture of ethylene glycol/water (EG–water, 20/80wt%). The experiments are conducted at various volume fractions between 0% and 4% and a temperature range of 15–60°C. Some...

This paper presented the whole year performance of a novel kind of microheat pipe array (MHPA) flat plate solar water heater. The structure and characters of the novel MHPA-FPC were presented. To quantify the performance of the novel MHPA-FPC SWH, a whole year thermal performance experiment was...