Theoretical basis and practical implementation of “bi-refrigerant” and “two-compressor” refrigeration machine schemes

Abstract

The operating conditions of a refrigeration machine determine its energy efficiency. Some industries, particularly the food industry, are characterized by seasonal (short-term) consumption of cold in the low-temperature range (−40℃ and below) when rapid freezing of the product is required to achieve high quality because of finely dispersed crystallization of moisture and a “shock” temperature for psychrophilic microorganisms. To solve this problem, the periodic use of a low-temperature refrigerant, which, from a rational technical point of view, is not always combined with the constant required temperature of refrigerated storage because of possible operation under vacuum conditions and other difficulties, is advised. The difference between the temperature regime of the required short-term (seasonal or periodic) processing and the constant (main) temperature regime (e.g., refrigerated storage of products) often reaches 20℃ or more, which imposes certain restrictions on the design or operation of the refrigeration machine. In this regard, small and medium-sized refrigeration machines with the capability to operate on two refrigerants (e.g., low and medium temperatures, with periodic automatic mutual replacement) are promising. Such a refrigeration machine is referred to as “bi-refrigerant” in this study. The aforementioned difficulties are also solved by the proposed scheme of a “two-compressor” refrigeration machine, in which the possibility of its operation is realized during periodic change of modes from one stage to two stages, and vice versa, according to the need for the corresponding differences in boiling and condensation pressures.

BACKGROUND: Environmental conditions and boiling point impose certain requirements on the selection of refrigerant and the design of the refrigeration machine, which often necessitates the division of the design period of operation of the refrigeration machine into two seasons, i.e., summer and winter, or the main operating mode (e.g., refrigerated storage) and nonessential (e.g., freezing seasonal or periodically supplied products to the refrigerator). This need may be especially acute in seasonal refrigerators and refrigerators operating under the conditions of large differences in ambient temperatures that periodically occur in some geographic areas. The need for a two-season (“bi-refrigerant”) refrigeration machine arises not due to fluctuations in the conversion coefficient under different environmental conditions (although this does occur) or a change in operating mode from the refrigeration cycle to the heat cycle (heat pump) but due to the seasonality of the supply of products subject to primary processing (quick freezing).

AIMS: This work aims to provide theoretical justification for the practical implementation of the “bi-refrigerant” and “two-compressor” refrigeration machine schemes.

MATERIALS AND METHODS: A theoretical investigation method was used to propose schemes for “bi-refrigerant” and “two-compressor” refrigeration machines, was used. The objects of the study were the diagrams of vapor compression refrigeration machines.

RESULTS: A schematic diagram of a “bi-refrigerant” refrigeration machine operating by periodically replacing “seasonal” refrigerants has been developed. A schematic diagram of a “two-compressor” refrigeration machine, which provides the possibility of periodically changing a one-stage to a two-stage cycle, has been presented. A diagram of the automatic control of the proposed solutions is presented using the example of a “bi-refrigerant” refrigeration machine. Mathematical support and justification of the developed schemes are also presented.

CONCLUSIONS: Our investigation revealed the theoretically justified possibility of using “bi-refrigerant” and “two-compressor” refrigeration machine schemes, e.g., in industries with seasonal short-term supply of short-term products subject to rapid (low-temperature) freezing or in other industries that require periodic changes in the boiling point of the refrigerant. Delaying factors in the application of the proposed “bi-refrigerant” refrigeration machine design may be the selection of compressor oil capable of operating on two refrigerants and the need to carefully solve the problem of circulation and its return to the compressor. However, this problem can be solved.

Keywords

seasonal refrigeration machine / two-compressor refrigeration machine / energy efficiency of refrigeration machine

References

[1] Arkharov AM, Shishov VV, Talyzin MS. Entropiynostatisticheskiy analiz nizkotemperaturnykh kholodil'nykh tsiklov i vybor na ego osnove optimal'noy sistemy kholodosnabzheniya magazine. Refrigeration Technology. 2016;105(3):30–34. (In Russ). doi: 10.17816/RF99047

[2] Архаров А.М., Шишов В.В., Талызин М.С. Энтропийностатистический анализ низкотемпературных холодильных циклов и выбор на его основе оптимальной системы холодоснабжения магазина // Холодильная техника. 2016. Т. 105, № 3. C. 30–34. doi: 10.17816/RF99047

[3] Gorbachev MV, Dyachenko YuV. Estimation of irreversible losses of thermodynamic efficiency of real cycles of an air-refrigeration machine. Nauchnyy vestnik NGTU. 2009;4(37):175–178. (In Russ).

[4] Горбачев М.В., Дьяченко Ю.В. Оценка необратимых потерь термодинамической эффективности реальных циклов воздушно-холодильной машины // Научный вестник НГТУ. 2009. № 4(37). С. 175–178.

[5] Malinina OS, Baranenko AV. Solar cooling absorption lithium bromide machines for conditioning and water production. Vestnik Mezhdunarodnoy akademii kholoda. 2015;4:38–43. (In Russ).

[6] Малинина О.С., Бараненко А.В. Гелиохолодильные абсорбционные бромистолитиевые машины для кондиционирования и получения воды // Вестник Международной академии холода. 2015. № 4. С. 38–43.

[7] Mirmov IN, Mirmov NI, Shchiptsov SA. Dvukhstupenchatye kholodil'nye mashiny kombinirovannogo tipa. Refrigeration Technology. 2018;107(7):26–31. (In Russ). doi: 10.17816/RF99422

[8] Мирмов И.Н., Мирмов Н.И., Щипцов С.А. Двухступенчатые холодильные машины комбинированного типа // Холодильная техника. 2018. Т. 107, № 7. C. 26–31. doi: 10.17816/RF99422

[9] Mirmov IN, Mirmov NI. Ispol'zovanie solnechnoy energii i vtorichnykh istochnikov teploty dlya polucheniya kholoda. Refrigeration Technology. 2011;100(9):44–48. (In Russ). doi: 10.17816/RF98107

[10] Мирмов И.Н., Мирмов Н.И. Использование солнечной энергии и вторичных источников теплоты для получения холода // Холодильная техника. 2011. Т. 100, № 9. C. 44–48. doi: 10.17816/RF98107

[11] Kolosov MA. Teorema ob ideal'nom tsikle teploispol'zuyushchey kholodil'noy mashiny. Refrigeration Technology. 2014;103(4):42–45. (In Russ). doi: 10.17816/RF98745

[12] Колосов М.А. Теорема об идеальном цикле теплоиспользующей холодильной машины // Холодильная техника. 2014. Т. 103, № 4. C. 42–45. doi: 10.17816/RF98745

[13] Babakin BS. Refrigerants, oils, refrigeration system service. Ryazan: Uzorechye; 2003. (In Russ).

[14] Бабакин Б.С. Хладогенты, масла, сервис холодильных систем. Рязань: Узоречье, 2003.

[15] Rogov IA, Kutsakova VE, Filippov VI, et al. Cold canning of food products. Moscow: KolosS; 2002. (In Russ).

[16] Рогов И.А., Куцакова В.Е., Филиппов В.И., и др. Консервирование пищевых продуктов холодом. М.: КолосС, 2002.

[17] Baranenko AV, Kutsakova VE, Borzenko EI, et al. Refrigeration technology of food products: a textbook for universities: in 3 parts. Part I. Thermophysical fundamentals. St. Petersburg: GIORD; 2007. (In Russ).

[18] Бараненко А.В., Куцакова В.Е., Борзенко Е.И., и др. Холодильная технология пищевых продуктов: учебник для вузов: в 3 частях. Часть I. Теплофизические основы. СПб.: ГИОРД, 2007.

[19] Semenov GV. Vacuum freeze drying. Moscow: DeLi plyus; 2013. (In Russ).

[20] Семенов Г.В. Вакуумная сублимационная сушка. М.: ДеЛи плюс, 2013.

[21] Semenov GV, Kasyanov GI. Drying raw materials: meat, fish, vegetables, milk: textbook. allowance. Rostov-on-Don: Mart; 2002. (In Russ).

[22] Семенов Г.В., Касьянов Г.И. Сушка сырья: мясо, рыба, овощи, молоко: учеб.-практич. пособие. Ростов-на-Дону: Март, 2002.

[23] Shlyakhovetsky VM. Achievements and problems of cryology: problems of theory and practice of application of cooling effects. Krasnodar; 2002. (In Russ).

[24] Шляховецкий В.М. Достижения и проблемы криологии: задачи теории и практики применения охлаждающих эффектов. Краснодар, 2002.

[25] Erlikhman VN, Fatykhov YuA. Canning and processing of food products at subzero temperatures. Kaliningrad: KGTU; 2004. (In Russ).

[26] Эрлихман В.Н., Фатыхов Ю.А. Консервирование и переработка пищевых продуктов при отрицательных температурах. Калининград: КГТУ, 2004.

[27] Bolshakov SA. Refrigeration and food technology: textbook. Moscow: Akademiya; 2003. (In Russ).

[28] Большаков С.А. Холодильная техника и технология продуктов питания: учебник. М.: Академия, 2003.

[29] Galimova LV, Gundareva YuG, Kostyurin AV, et al. Modeling of thermodynamic analysis of a two-stage refrigeration machine. Vestnik AGTU. 2009;1(48):56–62. (In Russ).

[30] Галимова Л.В., Гундарева Ю.Г., Костюрин А.В., и др. Моделирование термодинамического анализа двухступенчатой холодильной машины // Вестник АГТУ. 2009. № 1(48). С. 56–62.

[31] Korotkiy IA, Neverov EN, Prib IA, et al. Proektnye resheniya skhemy kholodil'noy mashiny s utilizatsiey teploty kondensatsii. Refrigeration Technology. 2020;109(6):30–33. (In Russ). doi: 10.17816/RF104056

[32] Короткий И.А., Неверов Е.Н., Приб И.А., и др. Проектные решения схемы холодильной машины с утилизацией теплоты конденсации // Холодильная техника. 2020. Т. 109. № 6. C. 30–33. doi: 10.17816/RF104056

[33] Korotkiy IA, Neverov EN, Korotkikh PS, et al. Development of a system for recycling condensation heat of refrigeration machines to reduce the dependence of the ice arena on urban heating and hot water supply systems. Vestnik Mezhdunarodnoy akademii kholoda. 2021;1:34–39. (In Russ).

[34] Короткий И.А., Неверов Е.Н., Коротких П.С., и др. Разработка схемы системы утилизации теплоты конденсации холодильных машин для снижения зависимости ледовой арены от городских систем отопления и горячего водоснабжения // Вестник Международной академии холода. 2021. № 1. С. 34–39.

[35] Kokorin OY, Tovaras NV, Firsov EV, et al. Energeticheskaya effektivnost' primeneniya kholodil'noy mashiny dlya teplo- i kholodosnabzheniya. Refrigeration Technology. 2011;100(6):40-44. (In Russ). doi: 10.17816/RF98077

[36] Кокорин О.Я., Товарас Н.В., Фирсов Е.В., и др. Энергетическая эффективность применения холодильной машины для тепло- и холодоснабжения // Холодильная техника. 2011. Т. 100, № 6. C. 40–44. doi: 10.17816/RF98077

[37] Morozyuk TV. Theory of refrigeration machines and heat pumps. Odessa: Negotsiant; 2006. (In Russ).

[38] Морозюк Т.В. Теория холодильных машин и тепловых насосов. Одесса: Негоциант, 2006.

[39] Plastinin PI. Piston compressors: textbook. manual for universities. Moscow: KolosS; 2006. (In Russ).

[40] Пластинин П.И. Поршневые компрессоры: учеб. пособие для вузов. М.: КолосС, 2006.

RIGHTS & PERMISSIONS

Eco-Vector