Design of an Improved Vertical Spiral Closed Loop Geothermal Heat Exchanger

Abstract

Geothermal heat pumps present a very intricate installation process and requires a vast amount of space which can cause a financial hurdle for most users. The geothermal system makes use of the constant ground temperature at the minimum of 5 ft depth with a thermal conductive working fluid and specified length of pipping. The system undergoes the necessary heat transfer that will be used as part of the heating or cooling process. In this study, an additively manufactured heat exchanger was designed and developed to address this issue. The design has an innovative coiled inner pipping to reduce the space needed for its installation, as well as combining the heat exchanger component with a drill bit design to simplify and reduce the cost of installation. We used CREO 8.0 to make a detailed drawing and CAD model of the system, which will then be simulated on ANSYS fluent software. During the simulation we studied the performance of heat transfer. In addition, this study also analyzes the coefficient of heat transfer and fluid pressure drop as a function of Reynolds number. For production of the system an additive manufacturing technique was used to manufacture the prototype.