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Convective Boiling Two-phase Flow in Trapezoidal Microchannels : Part 2-Heat Transfer Characteristics

사다리꼴 미세유로의 대류비등 2상유동 : 2부-열전달 특성

  • Received : 2011.03.28
  • Accepted : 2011.10.06
  • Published : 2011.11.10

Abstract

Characteristics of flow boiling heat transfer in microchannels were investigated experimentally. The microchannels consisted of 9 parallel trapezoidal channels with each channel having 205 ${\mu}m$ of bottom width, 800 ${\mu}m$ of depth, $3.6^{\circ}$ of sidewall angle, and 7 cm of length. Tests were performed with R113 over a mass velocity range of 150~920 $kg/m^2s$, heat flux of 10~100 $kW/m^2$ and inlet pressures of 105~195 kPa. Flow boiling heat transfer coefficient in microchannels was found to be dominated by heat-flux. However the effect of mass velocity was not significant. Contrary to macrochannel trends, the heat transfer coefficient was shown to decrease with increasing thermodynamic equilibrium quality. A new correlation suitable for predicting flow boiling heat transfer coefficient was developed based on the laminar single-phase heat transfer coefficient and the nucleate boiling dominant equation. Comparison with the experimental data showed good agreement.

Keywords

References

  1. Chen, J. C., 1966. Correlations for boiling heat transfer to saturated fluids in convective flow. Ind. Chem. Proc. Des. Dev., Vol. 5, No. 3, pp. 322-339. https://doi.org/10.1021/i260019a023
  2. Warrier, G. R., Dhir, V. K., and Momoda, L. A., 2002. Heat transfer and pressure drop in narrow rectangular channel, Experimental Thermal and Fluid Science, Vol. 26, pp. 53-64. https://doi.org/10.1016/S0894-1777(02)00107-3
  3. Steinke, M. E. and Kandlikar, S. G., 2004, An experimental investigation of flow boiling characteristics of water in Parallel microchannels, J. of Heat Transfer, Vol. 126. pp. 518-526. https://doi.org/10.1115/1.1778187
  4. Kandlikar, S. G., 1990, A general correlation for two-phase flow boiling heat transfer coefficient inside horizontal and vertical tubes, ASME J. Heat Transfer, Vol. 112, pp. 219-228. https://doi.org/10.1115/1.2910348
  5. Lee, J. and Mudawar, I., 2005, Two-phase flow in high-heat-flux micro-channel heat sink for refrigeration cooling applications:Part II-heat transfer characteristics, Int. J. Heat Mass Transfer, Vol. 48, pp. 941-955. https://doi.org/10.1016/j.ijheatmasstransfer.2004.09.019
  6. Lee, P. and Garimella, S. V., 2008, Saturated flow boiling heat transfer and pressure drop in silicon microchannel arrays, Int. J. Heat Mass Transfer, Vol. 51, pp. 789-806. https://doi.org/10.1016/j.ijheatmasstransfer.2007.04.019
  7. Kim, B. and Kim, G., 2008, Experimental studies on single-phase flow and heat transfer in microchannels, J. of SAREK, Vol. 20, No. 12, pp. 795-801.
  8. Kline, S. J., 1985, The Purposes of Uncertainty Analysis, J. Fluids Eng., Vol. 107, pp. 153- 160. https://doi.org/10.1115/1.3242449
  9. Zivi, S. M., 1964, Estimation of steady-state steam void fraction by means of the principle of minimum entropy production, Trans. ASME, J. Heat Transfer, Vol. 86, pp. 247-252. https://doi.org/10.1115/1.3687113
  10. Kim, B. and Kim, G., 2011, Convective Boiling Two-phase Flow in Trapezoidal Microchannels: Part 1-Pressure Drop Characteristics, J. of SAREK, Vol. 23, No. 1, pp. 87-94.
  11. Li, Z., Tao, W. Q., and He, Y L., 2006, A numeircal study of laminar convective heat transfer in microchannel with non-circular crosssection, Int. J. of Thermal Science, Vol. 45, pp. 1140-1148. https://doi.org/10.1016/j.ijthermalsci.2006.01.011
  12. Lockhart, R. W. and Martinelli, R. C., 1949, Proposed correlation of data for isothermal twophase two-component flow in pipes, Chem. Eng. Prog., Vol. 45, pp. 39-48.