International Scientific Journal

Thermal Science - Online First

online first only

Experimental study on boiling heat transfer in negative-pressure flowing water in a vertical annular tube

To study energy recovery from low-temperature wastewater during industrial production, a water-boiling heat-transfer experimental device was built. A casing evaporator with a length of 1450 mm, an inner tube diameter of 30 mm, and an annular space gap of 14.2 mm is taken as the main research object. The boiling heat transfer characteristics of water in the annular tube area of the casing evaporator were experimentally studied by adjusting the inlet temperature (60-85°C) of hot water and the pressure in the annular tube (12.1-57.6 kPa). The results show that, as the pressure of the system decreases, the boiling phenomenon in the annular tube becomes more intense and the convective heat transfer coefficient increases. The boiling flow and average surface convective heat transfer enhancement rates (β) were 2.2 and 1.5 when an initial pressure of 1 kPa was used. When the flow rate of the working medium in the annular tube was 1.69 kg•m−2•s−1, the convective heat transfer coefficient gradually increased with the temperature and then stabilized when the inlet temperature reached between 80°C and 85°C. These results reveal the characteristics of boiling-water heat transfer in an annular tube and aid in the design of heat pipe systems for waste-heat recovery.
PAPER REVISED: 2022-05-10
PAPER ACCEPTED: 2022-05-11
  1. Quan, G. H., et al., Treatment and comprehensive utilization technology of printing and dyeing wastewater, Water & Wastewater Engineering, 1(2000), 02, pp. 40-42,1.
  2. Dehghani, M. J., Yoo, C. K., Modeling and extensive analysis of the energy and economics of cooling, heat, and power trigeneration (CCHP) from textile wastewater for industrial low-grade heat recovery, Energy Conversion and Management, 205 (2020), p. 112451.
  3. Song, R. W., et al., The application of new heat pipe technology in chemical production is explored, Henan chemical industry, 36 (2019), 12, pp. 43-45.
  4. Remeli, M. F., et al., Simultaneous power generation and heat recovery using a heat pipe assisted thermoelectric generator system, Energy Conversion and Management, 91 (2015), pp. 110-119.
  5. Srimuang, W., Amatachaya, P., A review of the applications of heat pipe heat exchangers for heat recovery, Renewable and Sustainable Energy Reviews, 16 (2012), 6, pp. 4303-4315.
  6. Guo, Z. J., et al., Application of pump-assisted separate heat pipe on dehumidifying enhancement in air conditioning system, Applied Thermal Engineering, 98 (2016), pp. 374-379.
  7. Kalita S, et al., Experimental study of nucleate pool boiling heat transfer on microporous structured by chemical etching method, Thermal Science and Engineering Progress, 26(2021), p. 101114.
  8. Kang, M.-G., Pool boiling heat transfer on the tube surface in an inclined annulus, International Journal of Heat and Mass Transfer, 53 (2010), 15, pp. 3326-3334.
  9. Chen, B., et al., Fluid dynamics and heat transfer investigations of swirling decaying flow in an annular pipe Part 1: Review, problem description, verification and validation, International Journal of Heat and Mass Transfer, 97 (2016), pp. 1029-1043.
  10. Xu, Y., Study of critical heat flow density experimental platform, Journal of Engineering for Thermal Energy and Power, 35 (2020), 05, pp. 92-96, 118.
  11. Miao S. S., et al., Visualization experiment and regulation of the flow boiling process in the evaporator, Journal of Engineering Thermophysics, 42 (2021), 07, pp. 1827-1831.
  12. Jige, D., Inoue, N., Boiling heat transfer, pressure drop, and flow pattern in a horizontal square minichannel, International Journal of Heat and Fluid Flow, 78 (2019), p. 108433.
  13. Ma, X., Experimental study on heat exchange characteristics of boiling in horizontal 3D reinforced tube, Ph. D. Thesis. Qingdao University of Science and Technology, (2020).
  14. Mishima, K., et al., Some characteristics of gas-liquid flow in narrow rectangular ducts, International Journal of Multiphase Flow, 19 (1993), 1, pp. 115-124.
  15. Situ, R., et al., Photographic study of bubble behaviors in forced convection subcooled boiling, International Journal of Heat and Mass Transfer, 47 (2004), 17, pp. 3659-3667.
  16. Pan L. M., et al., Subcooled flow boiling heat transfer performance in a vertical rectangular narrow slot, Journal of Thermal Science and Technology, 1(2002), 02, pp. 185-188.
  17. Zambrana, J., et al., Vertical tube length calculation based on available heat transfer coefficient expressions for the subcooled flow boiling region, Applied Thermal Engineering, 28 (2008), 5, pp. 499-513.
  18. Moffat, R.J., Describing the uncertainties in experimental results, Experimental Thermal and Fluid Science, 1 (1988), 1, pp. 3-17.