Paper Conference

Proceedings of eSim 2020: 11th Conference of IBPSA-Canada


A Hybrid Numerical-Analytical Method to Evaluate Short-Term Temperatures Changes in Geothermal Boreholes

Carlos Prieto, Massimo Cimmino
Polytechnique Montréal, Canada

Abstract: The simulation of ground-source heat pump systems coupled to vertical geothermal boreholes is typicaly conducted using spatial and temporal superposition techniques on analytical solutions of the heat equation. While numerical methods offer greater flexibility in bore field configurations and physical processes that can be taken into account, they are seen as computationally inefficient when compared to their analytical counterparts. In the present research, a hybrid model is introduced for the simula tion of single U-tube geothermal boreholes, with the U-tube simplified as a single equivalent pipe. The model encompasses a finite difference scheme for time derivatives to simulate heat transfer in the grout and the ground, and an analytical solution to evaluate the fluid temperature andheat transfer rate profiles along the equivalent pipe. The model is compared against a reference finite element model and the experimental data set of Beier et al. (2011).