EXPERIMENTAL STUDIES OF THE AIR FLOW HEATING PROCESS IN A VERTICAL SOIL HEAT EXCHANGER

The article considers the possibilities of using the soil as a source of low-potential heat in Ukraine, where it maintains a constant temperature at a depth of more than 10 meters +9…12 °C throughout the year. This creates favorable conditions for efficient use of heat pumps. The analysis of technical means of extracting thermal energy from the surface layers of the soil shows that vertical soil heat exchangers are the most effective for achieving the required parameters of the microclimate in livestock premises. The study of the process of heating the air flow in the vertical soil heat exchanger was carried out under production conditions at the pig farm of the Agrofirma Napadivska Agricultural Company in the Vinnytsia region. To increase the efficiency of the clean air injection system, a U-shaped vertical soil heat exchanger is installed, which is connected to the ventilation system of the pig fattening room. Research was conducted at different levels of air flow (200, 500, 800 m³/hours) and air temperature in the soil heat exchanger, which was fixed six times a day. Indicators of climatic conditions were determined by measuring temperature and air humidity, as well as by monitoring temperature dynamics throughout the year. According to the results of experimental studies of the process of heating the air flow in a U-shaped vertical soil heat exchanger in production conditions, the dynamics of temperature changes throughout the year were determined. The obtained regression equations of the second order of changes in air flow temperature ΔTa and effective heat capacity NE from temperature Tin and expenses Qin air flow at the entrance to the U-shaped vertical soil heat exchanger.Statistical comparison of experimental data with theoretical dependence by the Pearson correlation coefficient – 0,95 and Fisher's test – F = 1,93 < Fт = 2,98 indicates the high adequacy of theoretical dependencies.