Experimental investigation of ground source heat pipes

The adverse effects of icing on highways, airports and sidewalks are common in winter. As an alternative to classical methods for the prevention of icing, ground-source heat pipes are of interest to researchers. Ground source heat pipes can use the soil as a heat source and prevent icing on the surface by the heat energy carried by the heat pipe. The aim of this study is to determine the heat flux that the ground source heat pipe can carry by considering the source temperature. For this purpose, four different elbow type heat pipes were produced. These heat pipes were tested in three different groups. Firstly, the heat flux that elbow type heat pipes can carry by giving heat from the evaporator area is determined. Secondly, these heat pipes were operated as ground source and their heat carrying capacity was determined. Finally, it has been observed to what extent the icing on a concrete surface can be prevented by these heat pipes. In the first group of experiments, it was observed that the heat flux carried by the heat pipe increased with the increase of the diameter and the internal temperature of the heat pipe when the heat was supplied from outside the evaporator section of the heat pipe. In the same working conditions, when the surface heat fluxes of the evaporator area of the heat pipes of different diameters were compared, the highest heat flux was observed in the heat pipe with a diameter of 18 mm. Similar results were obtained for 28 and 35 mm heat pipes. When these heat pipes were operated at low soil temperatures, similar results were obtained from the previous test results. In order to determine the area where the heat pipes can prevent icing on the concrete surface, the soil and ambient temperature were changed in a controlled cold room, and the temperature distribution on the concrete surface was determined and the results were evaluated graphically. As a result, it has been found that the icing on the surface can be prevented by choosing suitable working fluid, pipe diameter and heat pipe length for elbow type ground source heat pipes. This study is expected to contribute to a better understanding of the ground-source heat pipes and the spread of their applications.