Comparison between analytical and numerical models for ground heat exchanger field sizing

Geothermal energy is a promising renewable energy source that utilizes thermal energy stored in the Earth’s crust. Shallow geothermal energy, specifically ground-source heat energy, has gained popularity due to its energy efficiency and environmental benefits, making it well-suited for residential and small-scale commercial buildings. Geothermal heat pumps (GHPs) are a well-known application of shallow geothermal energy, providing heating in the winter and cooling in the summer by extracting and returning heat to the ground. Accurate modeling and simulation of the source side behavior are crucial for designing and operating efficient geothermal air conditioning systems. This study focuses on modeling the heat exchange processes in the ground and its effects for a long time, evaluating also the groundwater's role in heat transfer in a closed-loop geothermal heat exchangers field at Trinity College, Dublin. The objective of the work is to compare the line source conductance-based model (EED) used for the original design with a numerical model (Feflow), to evaluate the differences in system performance and thermal ground effects. By constructing a 3D numerical model of the subsurface using Feflow software, a detailed analysis of heat transfer processes within the geothermal collector is conducted. the In this study the variations in temperature and flow rate heat carrier fluid inside the heat exchangers probes are analyzed to detect the heat exchange capacity and energy efficiency of the geothermal heat pump system. By the comparison of the temperatures generated by the Feflow forward model with those obtained from the EED model. has been possible to understand the limits of the different analytical and numerical approaches. The results obtained from this comparative analysis provide valuable insights into the performance of different geothermal models and emphasize the importance of using advanced modeling tools for the accurate evaluation of geothermal system performance. By examining the behavior of the source side, this study contributes to a better understanding of the interactions between groundwater, heat transfer processes, and the overall performance of geothermal heat pump systems. The findings highlight the significance of accurate modeling and simulation in optimizing system efficiency and achieving sustainable energy solutions, showing the potential of advanced numerical modeling techniques, such as Feflow, in accurately evaluating geothermal system performance and informing future design and operation decisions.

.Geothermal energy is a promising renewable energy source that utilizes thermal energy stored in the Earth’s crust. Shallow geothermal energy, specifically ground-source heat energy, has gained popularity due to its energy efficiency and environmental benefits, making it well-suited for residential and small-scale commercial buildings. Geothermal heat pumps (GHPs) are a well known application of shallow geothermal energy, providing heating in the winter and cooling in the summer by extracting and returning heat to the ground. Accurate modeling and simulation of the source side behavior is crucial for designing and operating efficient geothermal air conditioning systems. This study focuses on modeling the heat exchange processes into the ground and its effects for a long time, evaluating also the groundwater role on heat transfer in a closed-loop geothermal heat exchangers field at Trinity College, Dublin. The objective of the work is to compare the line source conductance-based model (EED) used for the original design with a numerical model (Feflow), to evaluate the differences in system performance and thermal ground effects. By constructing a 3D numerical model of the subsurface using Feflow software, a detailed analysis of heat transfer processes within the geothermal collector is conducted. the In this study the variations in temperature and flow rate heat carrier fluid inside the heat exchangers probes are analyzed in order to detect the heat exchange capacity and energy efficiency of the geothermal heat pump system. By the comparison of the temperatures generated by the Feflow forward model with those obtained from the EED model it. has been possible to understand the limits and plus of the different analytical and numerical approaches. The results obtained from this comparative analysis provide valuable insights into the performance of different geothermal models and emphasize the importance of using advanced modeling tools for the accurate evaluation of geothermal system performance. By examining the behavior of the source side, this study contributes to a better understanding of the interactions between groundwater, heat transfer processes, and the overall performance of geothermal heat pump systems. The findings highlight the significance of accurate modeling and simulation in optimizing system efficiency and achieving sustainable energy solutions, showing the potential of advanced numerical modeling techniques, such as Feflow, in accurately evaluating geothermal system performance and informing future design and operation decisions.