Flow structures during refrigerants condensation

• Autorzy: Sikora M.
• Języki publikacji: EN

Abstrakty

EN

For several years, in the world are carried out studies on the refrigerants condensation in minichannels. These studies are aimed at understanding the condensation process and facilitate the design of mini heat exchangers. It is very important to optimize heat transfer and drive power consumption of the is the knowledge of the processes occurring during refrigerants condensation in pipe minichannels. It is important in this case to make a individual flow structures maps for the refrigerants, due to the significant effect of flow structured formed in the minichannel on the heat transfer and flow resistance. Unfortunately, in relation to the number of publications about condensation in minichannels, the number of published flow maps is relatively small. Due to the fact that the condensation process takes place differently in the minichannels and conventional channels, there is no possibility of using the flow maps for conventional channels to identification flow patterns in minichannels. One of the most popular flow maps for the condensation in minichannels is the map created by Colleman and Garimella, which was made for the R134a refrigerant. The authors conducted their own experimental studies of refrigerants R134a, R404A and R407C condensation in pipe minichannels with an internal diameter d = 3.3 - 0.31 mm. These studies results were subjected to calculation identification of flow structures using the map of Colleman and Garimella. These results are compared with the criteria published on Thome and Cavallini flow maps.

Słowa kluczowe

EN

condensation; refrigerant; minichannel; flow pattern

PL

kondensacja; czynnik chłodniczy; minikanał; model przepływu

• Wydawca: Wydawnictwo Uczelniane Politechniki Koszalińskiej
• Czasopismo: Journal of Mechanical and Energy Engineering
• Rocznik: 2017
• Tom: Vol. 1, No 1
• Strony: 101--106
• Opis fizyczny: Bibliogr. 13 poz., rys., wykr.

Twórcy

autor

Sikora M.

• Faculty of Mechanical Engineering, Department of Power Engineering, Koszalin University of Technology, Raclawicka 15-17, 75-620, Koszalin, Poland

Bibliografia

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• 3. Bohdal T., Charun H., Sikora M. (2011): Comparative investigation of the condensation of R134a and R404A refrigerants in pipe minichannels. Int. J. of Heat and Mass Transfer, vol. 54, pp. 1963-1974.
• 4. Cavallini A., Del Col D., Doretti L., Matkovic M., Rossetto L., Zilio C. (2005): Two-Phase Frictional Pressure Gradient of R236ea, R134a and R410A inside Multi-Port Mini-Channels. Experimental Thermal and Fluid Science, vol. 29, pp. 861-870.
• 5. Coleman J., Garimella S. (2003): Two-Phase Flow Regimes in Round, Square and Rectangular Tubes During Condensation of Refrigerant R134a. Int. J. of Refrigeration, vol. 26(1), pp. 117-128.
• 6. Ewing M.E., Weinandy J.J., Christensen R,.N. (1999): Observations of two-phase flow patterns in a horizontal circular channel. Heat Transfer Engineering, vol. 20 (1), pp. 9-14.
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• 9. Łukaszuk M. (2005): Zastosowanie wykresu Taitela i Dublera do identyfikacji struktur przepływów dwufazowych w kanałach o małych średnicach. Materiały XIX Zjazdu Termodynamików, Sopot.
• 10. Łukaszuk M. (2010): Experimental investigation of two-phase steam flux In horizontal channels of small diameter. Heat Transfer Engineering, vol. 31 (4), pp. 331-334.
• 11. Michalska-Pożoga I., Tomkowski R., Rydzkowski T., Vijay Kumar Thakur (2016): Towards the usage of image analysis technique to measure particles size and composition in wood-polymer composites. Indus-trial Crops and Products, 92, 149-156.
• 12. Tabatabai A., Faghri A. (2001): A new two-phase flow map and transition boundary accounting for surface tension effects in horizontal miniature and micro tubes. J. of Heat Transfer, vol. 123, pp. 958-968.
• 13. Thome J.R. (2004-2008): Engineering Data Book III: Chapter 8 – Condensation inside tubes. Wolverine Tube, Inc.

Uwagi

PL

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017).