doi: 10.17586/2226-1494-2023-23-2-422-429

Modeling of heat-hydrodynamic processes in evaporators of low-temperature systems with intrachannel boiling of refrigerants

O. S. Apitsyna, A. A. Malyshev, A. V. Zaitsev, O. S. Malinina

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Apitsyna O.S., Malyshev A.A., Zaitsev A.V., Malinina O.S. Modeling of heat-hydrodynamic processes in evaporators of low-temperature systems with intrachannel boiling of refrigerants. Scientific and Technical Journal of Information Technologies, Mechanics and Optics, 2023, vol. 23, no. 2, pp. 422–429 (in Russian). doi: 10.17586/2226-1494-2023-23-2-422-429 

The introduction of new types of heat exchangers with phase transitions and the solution of problems of optimizing the design and operational characteristics are a priority within the framework of the energy saving program. Known methods for calculating the heat-hydrodynamic parameters of the flow of refrigerants often do not take into account the specifics of boiling processes at low temperatures as well as in channels with a small flow area. This paper presents the results of modeling heat transfer during the boiling of refrigerants in the channels of evaporators of heat and cold energy complexes, taking into account the true flow parameters. The proposed mathematical model of the boiling of the working substance in channels of various shapes is based on the true flow parameters which imply knowledge of the channel cross-sectional areas occupied by each of the phases. The value of the true volumetric steam content provides the most correct modeling of two-phase flows in a wide range of regime and geometric parameters. The paper uses the equations of material and heat balance in combination with the equation of heat transfer from the environment to the boiling refrigerant. The map of flow regimes is used as an empirical component. A program has been developed for calculating the proposed system of equations which is solved iteratively at each time step using the finite volume method. Comparison of calculation results with experimental data on models of round and rectangular channels with intracanal boiling of refrigerants at positive and negative saturation temperatures is performed. It is shown that the calculation error does not exceed 10 % for a round and 20 % for a rectangular flow section. The verification results showed the possibility of using the model in the framework of engineering calculations. The proposed mathematical model can be used as the basis for the calculation programs for existing evaporators and for the creation of new types of heat exchangers with in-tube boiling of the working substance. The proposed method allows optimizing both geometric and thermal-hydrodynamic parameters.

Keywords: heat transfer, intrachannel boiling, heat transfer modeling, true volumetric vapor content, material balance equation, heat balance equation, heat transfer equation

  1. Mezentseva N.N., Mezentsev I.V., Mukhin V.A. At nucleate boiling heat transfer zeotropic mixtures a horizontal tubes. VestnikNSU. Series: Physics, 2016, vol. 11, no. 3,pp. 46–52.(in Russian)
  2. Apitsyna O.S., Malyshev A.A., Malinina O.S., Arno M.D., Bubnov K.A., Zakharova V.Yu. Calculation of local heat transfer at refrigerant boiling in confined space. Journal of International Academy of Refrigeration, 2021, no. 2, pp. 79–87. (in Russian).
  3. Zhou Z., Fang X., Li D. Evaluation of correlations of flow boiling heat transfer of R22 in horizontal channels. The Scientific World Journal, 2013, vol. 2013, pp. 458797.
  4. Niño V.G., Hrnjak P.S., Newell T.A. Characterization of Two-phase Flow in Microchannels: ACRC Technical Report 202. University of Illinois at Urbana-Champaign, 2002.98 p.
  5. Lockhart R., Martinelli R. Proposed correlation of data for isothermal two-phase, two-component flow in pipes. Chemical Engineering Progress, 1949, vol. 45, no. 1, pp. 39–48.
  6. Saitoh S., Daiguji H., Hihara E. Correlation for boiling heat transfer of R-134a in horizontal tubes including effect of tube diameter. International Journal of Heat and Mass Transfer, 2007, vol. 50, no. 25-26, pp. 5215–5225.
  7. Bertsch S.S., Groll E.A., Garimella S.V. A composite heat transfer correlation for saturated flow boiling in small channels.International Journal of Heat and Mass Transfer, 2009, vol. 52, no. 7-8, pp. 2110–2118.
  8. Yan C., Wei C., Zhang S.S. Research on the flow boiling characteristics of water in a multi-furcated tree-shaped mini-channel. Advanced Materials Research, 2013, vol. 629, pp. 691–698.
  9. Kuntha U., Kiatsiriroat T. Boiling Heat Transfer Coefficient of R22 refrigerant and its alternatives in horizontal tube: small refrigerator scale. Songklanakarin Journal of Science and Technology, 2002, vol. 24, no. 2, pp. 243–253.
  10. Kawahara A., Mansour M.H., Sadatomi M., Law W.Z., Kurihara H., Kusumaningsih H. Characteristics of gas-liquid two-phase flows through a sudden contraction in rectangular microchannels. Experimental Thermal and Fluid Science, 2015, vol. 66, pp. 243–253.
  11. Shah M. Comprehensive correlation for dispersed flow film boiling heat transfer in mini/macro tubes. International Journal of Refrigeration, 2017, vol. 78, pp. 32–46.
  12. Mercado M., Wong N., Hartwig J. Assessment of two-phase heat transfer coefficient and critical heat flux correlations for cryogenic flow boiling in pipe heating experiments. International Journal of Heat and Mass Transfer, 2019, vol. 133, pp. 295–315.
  13. Goto D., Santoso A., Takehira T., Aslam A., Kawahara A., Sadatomi M. Pressure drop for gas and non-newtonian liquid two-phase flows across sudden expansion in horizontal rectangular mini-channel. Journal of Mechanical Engineering and Automation, 2016, vol. 6, no. 11–12, pp. 51−57.
  14. Tibiriçá C.B., Ribatski G. Flow boiling heat transfer of R134a and R245fa in a 2.3 mm tube. International Journal of Heat and Mass Transfer, 2010, vol. 53, no. 11-12, pp. 2459–2468.
  15. Khovalyg D., Baranenko A.V. Methods for calculating the pressure gradient of a two-phase flow when flowing in small channels. Journal of International Academy of Refrigeration, 2012, no. 1, pp. 3–10. (in Russian)
  16. Shashwat J., Prasanna J., Sateesh G. Modeling of pressure drop and heat transfer for flow boiling in a mini/micro-channel of rectangular cross-section. International Journal of Heat and Mass Transfer, 2019, vol. 140, pp. 1029–1054.
  17. Krause F., Schüttenberg S., Fritsching U. Modelling and simulation of flow boiling heat transfer. International Journal of Numerical Methods for Heat and Fluid Flow, 2010, vol. 20, no. 3, pp. 312–331.
  18. Malyshev A.A., Malinina O.S., Kalimjanov D.E., Sukhov P.S., Kuadio K.F. Comparative analysis of thermal exchange calculation for refrigerants boiling in channels. Journal of International Academy of Refrigeration, 2020, no. 1, pp. 34–39. (in Russian).
  19. Zaitcev A.V. Development of an algorithm for solving the Navier–Stokes equations for the flow of a cryogenic liquid in a pipe. Journal of International Academy of Refrigeration, 2011, no. 3, pp. 37–42. (in Russian)
  20. Malyshev A.A., Mamchenko V.O., Kisser K.V. Heat transfer and hydrodynamics of two-phase refrigerant flows. Study Guide. St. Petersburg, ITMO University, 2016, 116 p. (in Russian)
  21. Koshelev S.V. Improving the energy efficiency of the ship refrigerating machines by choosing rational refrigerant boiling modes in evaporators. Dissertation for the degree of candidate of technical sciences. Kaliningrad, 2019, 213 p. (in Russian)
  22. Zemskov B.B. Study of the thermal interchange and hydrodynamics during freon boiling in vertical channels of complex shape. Dissertation for the degree of candidate of technical sciences. Leningrad, 1978, 216 p. (in Russian)

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