Experimental Study on Temperature Control Optimization of Ground Source Heat Pump Horizontal Headers

Abstract

The energy loss of ground source heat pump horizontal headers cannot be ignored. Based on the similarity theory and the principle of the orthogonal test, a sandbox experiment platform was built to study the temperature change rule of the horizontal header under the action of multiple factors and the influence of the temperature change on the U-tube heat exchange capacity. The results show that: (1) The influence degree of each factor on the horizontal header is as follows: buried depth > surface temperature > covering material > flow in the pipe; (2) Under the two extreme conditions, the temperature rise difference of the horizontal header water supply section is 0.25 and that of the return section is 0.29 , the heat transfer difference of the water supply section is 91 W and that of the return section is 105 W and the heat exchange difference of the U-tube is 38.5 W; (3) The temperature rise in the return section of the horizontal header causes the loss of cold in the pipe, but the temperature rise in the water supply section promotes the heat exchange of the U-tube. Finally, the optimization methods and construction recommendations are put forward.