Analyzing heat transfer in a horizontal geothermal heat exchanger using numerical methods

Abstract

Given the growing significance of renewable energy systems, researchers systems focus on optimizing heat transfer mechanisms. This study delves into the performance characteristics of a Slinky geothermal heat exchanger employing water as the working fluid. This study investigates how the step parameter of twisted tape affects hydrothermal parameters in Slinky heat exchangers, as well as the ideal depth of installation in the ground for improved performance. The numerical analysis results show that the Slinky heat exchanger shows superior thermal efficiency when employing a 200 mm pitch strip compared to the other two modes tested. During the first stage, the thermal performance coefficient peaked at 1.93 with a mass flow rate of 0.5 kg/s. Reducing the turbulator pitch increased fluid interaction and enhanced rotation within a larger fluid volume. Consequently, this augments heat transfer and improves the heat exchanger's overall thermal efficiency. Therefore, Slinky exchangers present a viable substitute for other ground-based heat exchangers by effectively enhancing heat transfer without inducing excessive pressure drop.

Keywords

• Thermal performance
• Slinky heat exchanger
• Geometrical parameters
• Finite volume method