Preprocessor for the generation of g-functions used in the simulation of geothermal systems

The objective of this paper is to present a general methodology for the calculation of thermal response factors, known as g-functions, of vertical borehole fields. The methodology accounts for the time variation of the heat extraction rates of individual boreholes. In addition, the original concept of the g-functions is extended to include variable borehole lengths and buried depths. Finally, the methodology is implemented into MATLAB with a convenient graphical user interface which pre-processes the hourly values of the thermal response factors for use in energy simulation programs.