CONSTRUCTION  
Heat Supply and Ventilation

DOI.org/10.5281/zenodo.896976

Zhurmilova I., Shtym A.

IRINA ZHURMILOVA, Candidate of Engineering Sciences, Associate Professor, e-mail: zhurmilova.ia@dvfu.ru
ALLA SHTYM, Candidate of Engineering Sciences, Professor, e-mail: shtym_alla@mail.ru
Department Engineering Systems of Buildings and Constructions, School of Engineering 
Far Eastern Federal University
8 Sukhanova St., Vladivostok, Russia, 690091

The influence of the thermophysical soil properties on the emergence of a geothermal field in the collecting system for the low-potential ground energy

Abstract: The use of renewable energy sources contributes to reducing the use of fossil fuels and improving the environmental situation which is an urgent task of today. Vertical ground heat exchangers extract the low-potential thermal energy of the ground mass lying below 10-15 m from the ground level and transfer it to the geothermal heat pumps. The low-potential energy collection systems with vertical ground heat exchangers do not require large areas, and do not depend on the intensity of solar radiation incident on the surface. They work effectively in virtually all types of geological environments, with the exception of the soils having low thermal conductivity, such as dry sand or gravel. In this paper, we propose an authorial method of calculating the distance between boreholes with ground heat exchangers taking into account the heat transfer process between the ground mass and the hydraulic fluid in the heat exchanger tubes eliminating the freezing of the boreholes. The application of the method makes it possible to choose the best option to shape a borehole field with soil heat exchangers for a specific construction area taking into consideration the thermal properties of the soil and to create an efficient and stable source of low-potential energy for geothermal heat pumps. A nomogram is presented which makes it possible to determine the distance between the boreholes ensuring a reliable and efficient operation of the geothermal heat pumps during the entire period of their operation without degrading the thermal physical properties of the soil.

Key words: low-potential energy, heat collection system, ground, freezing of borehole, ground heat ex-changer, heat flow.

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