Performance evaluation of different types of ground source heat exchangers in a hot and dry climate

Abstract

Most of the energy consumption in a hot and dry area is used for the air-conditioning systems. This study aims to investigate the possibility of reducing the electricity consumption in air conditioners using ground cold energy to cool the hot fluid in the pipes.Several experiments were carried out to investigate the performance of the proposed system to be used in the weather conditions of Baghdad city (i.e., hot and dry).Two configurations of ground source heat exchangers (GSHEs) were developed and constructed. The first configuration comprised coil type with two different materials (copper and polyvinyl chloride [PVC]). The second configuration was the 3U type, which was made from copper, PVC, and galvanized. Three water flow rates were considered (5, 10, and 15 L/min) with water inlet temperatures (80°C, 70°C, and 60°C). The experiments' results showed that the type of material of the pipe has a significant influence on both the heat transfer effectiveness and the system performance.Copper tubes were the best type of heat exchanger (type coil) to be used in this regard. The highest recorded values of the heat exchange rate were 5.81, 4.81, 2.72, 1.60, and 1.32 kW with an inlet temperature of 80°C and a flow rate of 5 L/min for the case of

Cooling of a PVT System Using an Underground Heat Exchanger: An Experimental Study

“…This means that the effect of surface temperature does not affect it; thus, this depth selection for installing the UHE was appropriate. The results of the study are completely agreement with those of Majeed et al 65 Figure 5 shows the effect of water flow rate on its temperatures in the underground exchanger as measured by thermocouples distributed along the exchanger tube. At point 1, the water temperature is approximately equal and less than the water temperature coming from the PVT system due to the loss of a large part of the heat along the pipe (4 m depth).…”

“…An area of agricultural land was chosen in the city of Baghdad to install and establish the GHE. The area of practical digging was 30 m 2 (6 × 5) m 2 , while the depth of drilling was 4 m. The drilling depth was chosen based on Majeed et al 65 results. Figure 1 illustrates all the drilling process during the experiments.…”

“…Underground Heat Exchanger Characterizations. In this practical research, the results of Majeed et al 65 study were used in determining the time and cost of digging and installing an UHE and then burying it. An area of agricultural land was chosen in the city of Baghdad to install and establish the GHE.…”

“…Test Procedure. The area chosen for UHE burial adopted Majeed et al 65 experiments to ensure the optimum conditions for the tests. Experiments were installed in an agricultural land in Baghdad city.…”

Design and optimization of ground‐coupled refrigeration heat exchanger in Dubai: Numerical approach

“…Otherwise, the system application will be unfeasible. In closed-loop systems, water circulates between the borehole heat exchanger and a chiller (or a heat pump) in a closed cycle, 11,13,17,[22][23][24][25] that is, no direct interaction between the circulating water and soil materials. This facilitates the heat exchanger installation even in soils saturated with contaminated water.…”