Numerical Investigation of the Long-Term Load Shifting Behaviors within the Borehole Heat Exchanger Array System

In the process of development and utilization a large-scale borehole heat exchanger (BHE) array system, phenomenon load shifting within BHE can be observed. this paper, OpenGeoSys software coupled with TESPy toolkit is used to establish comprehensive numerical model system (without depicting pump part), behaviors between BHEs different design parameters are studied. The results show that outlet temperature single generally rising, soil around has accumulated unbalanced heat. near fluctuates more obviously than distribution uneven. At end 15th year, center increased by 2 °C compared initial temperature, which was favorable in winter, but not conducive performance improvement summer. Further analysis changing inter-borehole spacing shows increase spacing, gradually weakened, maximum shifted central linear change spacing. After layout methods, we observe intensive is, behavior rate lower other layouts. With number BHEs, further enhanced. By analyzing proportion amount relative average value, it found will take longer time reach balance BHEs’ number. A shutdown part for certain period help improve long-term operational efficiency shallow ground source (GSHP) system.