SINGLE-CIRCUIT AND DUAL-CIRCUIT HEAT PUMP SYSTEMS. INTERRELATION OF PHYSICAL PROCESSES AND EFFICIENCY

• Date: 2019
• Author Affiliations: S. Goshovskyi — Ukrainian State Geological Research Institute 04114, 78A Avtozavodska St., Kyiv, Ukraine; O. Zurian — Ukrainian State Geological Research Institute 04114, 78A Avtozavodska St., Kyiv, Ukraine
• Keywords: keywords
• Main Authors: Goshovskyi, S., Zurian, O.
• Format: Article
• Language: Ukrainian
• Published: Institute of Renewable Energy National Academy of Sciences of Ukraine 2019
• Subjects: heat pump; dual-circuit heat pump; energy of environment; renewable energy sources.
• Online Access: https://ve.org.ua/index.php/journal/article/view/194
• Journal Title: Vidnovluvana energetika

It contains the theoretical analysis of special aspects of the use and technologies used for single and dual circuit heat pump systems. The analysis of major disadvantages of single circuit heat pump systems is conducted. It is analytically proved that heat exchange process occurs at variable temperatures of the heat source and heat sink and it causes stray load loss in an evaporator and condenser and, correspondently, it decreases the coefficient of performance of the heat pump system. Experiments proved that decrease of the coefficient of performance is not positively associated with increase of the temperature of supply heat transfer medium, but it has some acceleration caused by increase of the system heat loss related to increase of pressure and temperature. It demonstrates functioning model of the experimental dual circuit heat pump system developed and designed by UKRSGRI. It describes the research procedure. It contains specifications of measuring equipment used for the experimental system model and of software used for archiving and visualization of data obtained during research conduction. It states the results of scientific work received by theoretical calculations and experimental testing of the heat pump system efficiency depending on one or dual circuit version. The dependence of heat pump coefficient of performance on the number of circuits is shown. It explains the dependence of the heat pump system efficiency on characteristics of the primary source of low-grade heat and design features of the heat supply system. The conclusion is drawn that the dual circuit system with circuits connected in series is more efficient than the single circuit one. Ref. 8, tab. 8, fig. 4.