In this deliverable the main fundamental processes of heat transport relevant to the ground heat exchangers have been described. For the purpose of the project, only heat transport due to conduction will be considered in detail.
There is abundant literature concerning methods to calculate the thermal response of ground heat exchangers and design. Using a few selected references an introduction to analytical and numerical methods is presented. A description of the different implementations of analytical and numerical modeling and design software codes is presented as well.
The different methods are classified for strengths and weaknesses based on criteria including methodology, complexity, number of input parameters required, processes considered, flexibility with regard to geology and parameters relating to the actual ground heat exchanger. The aim has not been to arrive at a ranking, but only at an overview of the capabilities of the codes and the ease or complexity of use. Cost is of course also an important aspect but is currently not included.
Based on the overview of different methodologies and implementations a roadmap for the development of the GHEX engineering tool within the work package has been defined. This roadmap is based on the expertise of the different partners and works from a detailed level, using the results to derive simplified models that can be integrated into a final engineering design tool.