Heat transfer performance experiment and simulation of ground heat exchanger in low temperature condition

Experiments and simulates the impact on heat exchange and soil temperature distribution in continuous low temperature operation of ground heat exchangers. The measured heat transfer capacity in operation can be maintained at 60 W/m to 85 W/m without sensible decreasing, which meets the heat demand of ground-source heat pump system. Simulates the freezing condition by computational fluid dynamics software, and verifies the validity of the model in return water temperature, heat transfer capacity and temperature on external side of exchanger pipes by the experimental data. Further simulation results based on ideal conditions indicate that high heat transfer performance of ground heat exchanger can be achieved in low temperature operation condition by reasonable heat supplement, and the impact on soil temperature is controllable.