Numerical Validation of a New Analytical Solution for Helical (Earth-Basket) Type Ground Heat Exchangers
Title: Numerical Validation of a New Analytical Solution for Helical (Earth-Basket) Type Ground Heat Exchangers
MDPI AG, Processes 2023, Volume 11, Issue 5, 1418, Special Issue “Advances in Integrated Geothermal Energy Systems”
Authors: Reichl, Christoph (*1); Witte, Henk (*2)
*1 AIT Austrian Institute of Technology GmbH, Center for Energy, Sustainable Thermal Energy Systems,
Giefinggasse 4, 1210 Vienna, Austria
*2 Groenholland Geo Energy Systems, Valschermkade 26, 1059 Amsterdam, The Netherlands
Abstract: In this paper, we show that an analytical solution based on the Finite Line Source and G-function approach is both sufficiently fast and accurate for design calculations of ground heat exchangers with a complex (spiral) geometry. Detailed validations were performed for the steadystate and transient responses of analytical models with different time scales (10 h and 250 h). A comparison with a detailed computational fluid dynamics model (Ansys Fluent) and the analytical method for different boundary conditions showed a very good agreement (maximum root mean square error) smaller than 0.25 K.