Experimental investigation into heat exchange performance of three ground heat exchangers in winter in hot summer and warm winter zone

Establishes an experiment system for single U tube, double U tube and tube-in-tube heat exchangers, studies the variation of the heat exchange with time during heat pump continuous and intermittent operating separately. The results show that the heat exchange per unit well depth of the double U tube heat exchanger is the largest, that of the single U tube heat exchanger takes the second place and that of tube-in-tube heat exchanger last, and that the heat exchange performance during intermittent operating is better than that in continuous operating.