Thermal and visualisation study of the hfe7100 refrigerant condensation process

• Autorzy: Bohdal, Tadeusz , Sikora, Małgorzata , Formela, Karolina
• Języki publikacji: EN

Abstrakty

EN

Technological advances are contributing to the search for highly efficient energy designs, and increasing interest in compact heat exchangers. Indeed, small channel diameters determine large heat transfer coefficients and condition a significant heat transfer area about the overall volume of the heat exchanger, as well as a smaller amount of refrigerant flowing in the system. Nevertheless, the operat-ing stability and energy efficiency of compact heat exchangers are influenced by two-phase flow structures, which depend on thermal flow parameters. Knowledge of the structures formed during the condensation process is therefore essential for optimising the operation of re-frigeration and air-conditioning equipment. This article presents the results from experimental studies of the HFE7100 refrigerant, from the hydrofluorocarbon group, condensation process in mini-channels with hydraulic diameters dh = 2.0 mm, 1.2 mm, 0.8 mm and 0.5 mm. Thermal flow characteristics were determined, and the forming structures of two-phase flow were recorded. The results of visualisation were subjected to morphological image analysis, based on a special algorithm written in MATLAB software. The algorithm makes it possi-ble to determine the void fraction, which is necessary for calculating the vapour quality, as well as the area of vapour bubbles and their number, directionality and length along the x- and y-axes.

Słowa kluczowe

EN

condensation; mini-channels; flow structures; HFE7100

• Czasopismo: Acta Mechanica et Automatica
• Rocznik: 2024
• Tom: Vol. 18, no. 1
• Strony: 60--67
• Opis fizyczny: Bibliogr. 20 poz., rys., tab., wykr.

Twórcy

autor

Bohdal, Tadeusz,

autor

Sikora, Małgorzata,

autor

Formela, Karolina

• Faculty of Mechanical Engineering, Department of Energy Engineering, Koszalin University of Technology, ul. Racławicka 15-17, 75-620 Koszalin, Poland,

Bibliografia

• 1. Wang Z, Xu Z, Luo L, Xia X, Peng D, Li X. Experimental investigation of condensation pressure drop of zeotropic refrigerant/oil mixtures in plate heat exchanger. International Journal of Refrigeration 2023; 149: 192-203. https://doi.org/10.1016/j.ijrefrig.2022.12.026
• 2. Mikielewicz D, Andrzejczyk R, Jakubowska B, Mikielewicz J. Com-parative study of heat transfer and pressure drop during flow boiling and flow condensation in minichannels. Archives of Thermodynam-ics. 2014; 35: 17–37. https://doi.org/10.2478/aoter-2014-0019
• 3. Jige D, Kikuchi S, Eda H, Inoue N, Koyama S. Two-phase flow characteristics of R32 in horizontal multiport minichannels. Flow vis-ualization and development of flow regime map. International Journal of Refrigeration 2018; 95: 156–164 https://doi.org/10.1016/j.ijrefrig.2018.09.005
• 4. Doretti L, Zilio C, Mancin S, Cavallini A. Condensation flow patterns inside plain and microfin tubes: A review. International Journal of Re-frigeration. 2013; 36: 567–587. https://doi.org/10.1016/j.ijrefrig.2012.10.021
• 5. Xiao J, Hrnjak P. A flow regime map for condensation in macro and micro tubes with non-equilibrium effects taken into account. Int J Heat Mass Transf. 2019; 130: 893–900. https://doi.org/10.1016/j.ijheatmasstransfer.2018.10.081
• 6. Soligo G, Roccon A., Soldati A. Mass-conservation-improved phase field methods for turbulent multiphase flow simulation. Acta Mech. 2019; 230: 683–696. https://doi.org/10.1007/s00707-018-2304-2
• 7. Coleman JW, Garimella S. Two-phase flow regimes in round, square and rectangular tubes during condensation of refrigerant R134a. In-ternational Journal of Refrigeration 2003; 26: 117–128. https://doi.org/10.1016/S0140-7007(02)00013-0
• 8. Fronk BM, Garimella S. In-tube condensation of zeotropic fluid mixtures: A review. International Journal of Refrigeration 2013; 36: 534–561. https://doi.org/10.1016/j.ijrefrig.2012.11.030
• 9. Garimella Srinivas FBM. Encyclopedia of two-phase heat transfer and flow I. Fundamentals and Methods II. Condensation heat trans-fer. World Scientific 2016
• 10. Dziubiński M, Prywer J. Mechanika płynów dwufazowych. Wydawnic-two Naukowo Techniczne, Warszawa 2009
• 11. Sikora M. Modelowanie struktur przepływu dwufazowego podczas skraplania w minikanałach 2020
• 12. Ligus G, Zając D, Masiukiewicz M, Anweiler S. A New Method of Selecting the Airlift Pump Optimum Efficiency at Low Submergence Ratios with the Use of Image Analysis. Energies (Basel) 2019; 12: 735. https://doi.org/10.3390/en12040735
• 13. El Hajal J, Thome JR, Cavallini A. Condensation in horizontal tubes, part 1: two-phase flow pattern map. Int J Heat Mass Transf. 2003; 46: 3349–3363. https://doi.org/10.1016/S0017-9310(03)00139-X
• 14. Coleman JW, Garimella S. Characterization of two-phase flow pat-terns in small diameter round and rectangular tubes. Int J Heat Mass Transf. 1999; 42: 2869–2881. https://doi.org/10.1016/S0017-9310(98)00362-7
• 15. Bohdal T, Sikora M, Widomska K, Radchenko AM. Investigation of flow structures during HFE-7100 refrigerant condensation. Archives of Thermodynamics 2016; 36: 25–34. https://doi.org/10.1515/aoter-2015-0030
• 16. Al-Zaidi AH, Mahmoud MM., Karayiannis TG. Condensation flow patterns and heat transfer in horizontal microchannels. Exp Therm Fluid Sci. 2018; 90:153–173. https://doi.org/10.1016/j.expthermflusci.2017.09.009
• 17. Xiao J, Hrnjak P. A flow regime map for condensation in macro and microtubes with non-equilibrium effects taken into account. Int J Heat Mass Transf. 2019. https://doi.org/10.1016/j.ijheatmasstransfer.2018.10.081
• 18. Sikora M, Bohdal T. Heat and flow investigation of NOVEC649 refrigerant condensation in pipe minichannels. Energy 2020. https://doi.org/10.1016/j.energy.2020.118447
• 19. Sikora M, Bohdal T, Formela K. Experimental Study of HFE 7000 Refrigerant Condensation in Horizontal Pipe Minichannels. Materials. 2021; 14: 6886. https://doi.org/10.3390/ma14226886
• 20. Chen Y, Gao H, Liu H, Chen D, Jiang J., Ma Z. Experimental investi-gation on condensation regimes and transition boundary during bub-ble condensation in narrow rectangular channel. International Journal of Thermal Sciences 2023; 188: 108212 https://doi.org/10.1016/j.ijthermalsci.2023.108212

Identyfikatory

DOI

10.2478/ama-2024-0008