Analysis of the applicability of typical refrigerants to single-stage refrigerating machines for thermostating objects at temperature range of minus 50 ... minus 70°C

Abstract

Low-temperature refrigeration machines used for maintaining objects in a temperature range of −50–−70°C play an important role in numerous fields related to science and technology. For example, in medicine, these machines are used for the storage of biomedical objects and drugs. Moreover, in engineering and metallurgy technologies, these machines are used to improve the characteristics of structural materials, finished parts, etc.

Various types of steam-compression refrigerating machines based on the Linde throttling refrigeration cycle, typically using one-component or mixed refrigerants as a working medium, are traditionally used to obtain the desired temperatures in the refrigeration chamber.

This study presents the results of a computational analysis related to refrigerating machines for maintaining objects in a temperature range of −50–−70°C, using standard refrigerants produced on a large scale as the working fluids. The comparison between low-temperature vapor compression machines with one- and two-stage compression with respect to various refrigerants for generating a temperature of −60°C is presented herein. Rational fields for application of such machines are identified and recommendations for their improvement are provided in this study.

One of the areas of improvement related to low-temperature refrigeration machines is the use of zeotropic and azeotropic multicomponent mixtures as refrigerants formed using extremely environmentally friendly refrigerants with low ODP and GWP values.

Keywords

refrigeration machine / single-stage cycle / refrigerant / cycle analysis

References

[1] Kalnin IM, Fadekov KN. Evaluation of the efficiency of thermodynamic cycles of vapor compression refrigeration machines and heat pumps. Refrigeration Technology. 2006;3:16–25. (in Russ.)

[2] Калнинь И.М., Фадеков К.Н. Оценка эффективности термодинамических циклов парокомпрессионных холодильных машин и тепловых насосов // Холодильная техника. 2006. № 3. С. 16–25. (in Russ.)

[3] Glukhov SD, Makarov BA, Zherdev AA, et al. Modeling the characteristics of small refrigeration machines. Vestnik MGTU. Seriya Mashinostroenie. 2005; Special issue: 98–104. (in Russ.)

[4] Глухов С.Д., Макаров Б.А., Жердев А.А., и др. Моделирование характеристик малых холодильных машин // Вестник МГТУ. Серия Машиностроение. 2005. Специальный выпуск. С. 98–104. (in Russ.)

[5] Serdakov GS. Thermodynamic evaluation of cascade and multi-stage refrigeration cycles. Vestnik Mezhdunarodnoy akademii kholoda. 1999;4:36–38. (in Russ.)

[6] Сердаков Г.С. Термодинамическая оценка циклов каскадных и многоступенчатых холодильных машин // Вестник Международной академии холода. 1999. № 4. С. 36–38. (in Russ.)

RIGHTS & PERMISSIONS

Eco-Vector