Experimental Investigation of Condensation Heat Transfer on Vertical Hydrophilic-Hydrophobic Aluminium Surfaces

Document Type : Full Length Research Article

Authors

1 Department of Thermofluids, Faculty of Mechanical Engineering, University of Kashan, Iran

2 Department of Thermofluids, Faculty of Mechanical Engineering, University of Kashan, Iran. Energy Research Institute, University of Kashan, Iran.

Abstract

Condensation is an important heat transfer regime, with vast applications in industries such as power generation and cooling systems. In the present study, the changes in the coating thickness and geometry of hydrophobic areas were investigated on hydrophobic-hydrophilic plates and totally hydrophobic ones, and a no-coating plate was also studied experimentally for the condensation phenomenon. Considering the use of aluminium as the base material, tests such as lithography with positive photoresist was conducted to study the photoresist adhesion to the aluminium surface and its impact on heat transfer, as well as testing the lift-off process to remove the remaining photoresist at the final stage of producing the plates, to improve their surfaces and optimize the major parameters in the production stage. For this study, one type of totally hydrophobic surface and two types of hybrid hydrophobic-hydrophilic surfaces with different widths of hydrophobic and hydrophilic areas were produced, each type in three thicknesses of 200, 450 and 900 nm. Considering the different values of coating thicknesses, the width of the hydrophobic and hydrophilic areas, the heat transfer coefficient and heat flux were calculated for each plate, and the optimal conditions for each plate were determined. Compared to the uncoated plates, the heat transfer coefficient and heat flux for each plate with hybrid hydrophobic-hydrophilic surfaces (width of 860 μm for hydrophilic area and 970 μm for the hydrophobic, and thickness of 450 nm) registered increase by 1.44-2.01 and 1.43-1.81 times, respectively, which were the highest among the plates in the present study.

Keywords

Main Subjects


[1]  Ferreira, J.C.A. and Barbosa, J.R., 2020. Quantifying interfacial parameters of upward and downward annular flow condensation from high-speed visualization, J Braz. Soc. Mech. Sci. Eng., 42(158).
[2]   Li, B., Feng, L., Wang, L. and Dai, Y., 2021. Experimental investigation of condensation heat transfer and pressure drop of R152a/R1234ze(E) in a smooth horizontal tube, Heat Transfer Research, 52 (7), pp.35-54.
[3]   Ko, J.W., Jeon, D.S. and Kim, Y.L., 2018. Experimental study on film condensation heat transfer characteristics of R1234ze(E) and R1233zd(E) over horizontal plain tubes, J Mech Sci Technol., 32, pp.527–534.
[4]   Rao, Y., Li, H., Shen, S., Yang, Q., Zhang, G., Zhang, X., Li, M. and Duan, S., 2017. Water vapor condensation on the inner surface of an N95 filtering facepiece respirator, Heat Transfer Research, 50(3), pp.217-231.
[5]   Farahani, S.D. and Karami, M., 2019. Experimental estimation of local heat flux on boiling surface in a mini-channel, Int. J. Communications in Heat and Mass Transfer. 108, 104271.
[6]   Farahani, S.D. and Kowsary, F., 2012. Estimation local convective boiling heat transfer coefficient in mini channel, Int. J. Communications in Heat and Mass Transfer, 39(2), pp.304-310.
[7]   Karami, M., Davoodabadi Farahani, S., Kowsary, F. and Mosavi, A. 2020. Experimental estimation of temporal and spatial resolution of coefficient of heat transfer in a channel using inverse heat transfer method, Engineering Applications of Computational Fluid Mechanics, 14(1), pp.271-283.
[8]   Davar, H., Nouri, N.M. and Navidbakhsh, M., 2021. Enhancement of condensation heat transfer at aluminum surfaces via laser-induced surface roughening, J Braz. Soc. Mech. Sci. Eng., 43(346).
[9]   Schmidt, E., Schurig, W. and Sellschopp, W., 1930. Condensation of water vapour in film-and drop form, Zeitschrift Des Vereines Deutscher Ingenieure, 74, pp.544-544.
[10] Citakoglu, E., and Rose, J.W., 1968. Dropwise condensation-some factors influencing the validity of heat-transfer measurements, Int. J. Heat Mass Transf., 11(3), pp.523-537.
[11] Izumi, M., Kumagai, S., Shimada, R., and Yamakawa, N., 2004. Heat transfer enhancement of dropwise condensation on a vertical surface with round shaped grooves, Exp. Therm. Fluid Sci., 49(2), pp.243-248.
[12] Koch, G., Zhang, D.C., and Leipertz, A., 1997. Condensation of steam on the surface of hard coated copper discs, Heat and Mass Transfer., 32(22), pp.149-156.
[13] Majumdar, A., and Mezic, I., 1999. Instability of ultra-thin water films and the mechanism of droplet formation on hydrophilic surfaces,” J. Heat Mass Transf., 121(4), pp.964-971.
[14] Vemuri, S., and Kim, K.J., 2006. An experimental and theoretical study on the concept of dropwise condensation, Int. J. Heat Mass Transf., 49(3), pp.649-657.
 [15] Tianqing, L., Chunfeng, M. Xiangyu, S. and Songbai, X., 2007. Mechanism study on formation of initial condensate droplets, The American Institute of Chemical Engineers Journal, 53(4), pp.1050–1055.
[16] Ma, X.-H., Zhou, X.-D., Lan, Z., Yi-Ming, L.I., and Zhang, Y., 2008. Condensation heat transfer enhancement in the presence of non-condensable gas using the interfacial effect of dropwise condensation, Int. J. Heat Mass Transf., 51(7), pp.1728-1737.
[17] Boreyko, J.B., and Chen, C.-H., 2009. Self-propelled dropwise condensate on superhydrophobic surfaces, Phys. Rev. Lett., 103(18), 184501.
[18] Talesh Bahrami, H.R., Azizi, A. and Saffari, H., 2020. An Empirical Study on Dropwise Condensation Occurred on Surfaces Hydrophobized Using a Single-Step Electrodeposition, Amirkabir Journal of Mechanical Engineering, 52(6), pp.1397-1412.
[19] Ghosh, A., Beaini, S., Zhang, B.J., Ganguly, R., and Megaridis, C.M., 2014. Enhancing Dropwise Condensation through Bioinspired Wettability Patterning, Langmuir, 30, pp.13103-13115.
[20] Peng, B., Ma, X., Lan, Z., Xu, W., and Wen, R., 2015. Experimental investigation on steam condensation heat transfer enhancement with vertically patterned hydrophobic–hydrophilic hybrid surfaces, Int. J. Heat Mass Tran., 83(4), pp.27-38.
[21] Peng, B., Ma, X., Lan, Z., Xu, W., and Wen, R., 2014. Analysis of condensation heat transfer enhancement with dropwise-filmwise hybrid surface: Droplet sizes effect, Int. J. Heat Mass Trans., 77, pp.785–794.
[22] Ji, X., Zhou, D., Dai, C., and Xu, J., 2019. Dropwise condensation heat transfer on superhydrophilic-hydrophobic network hybrid surface, Int. J. Heat Mass Trans., 132, pp.52-67.
[23] Oestreich, J.L., van der Geld, C.W.M., Oliveira, J.L.G. and da Silva, A.K., 2019. Experimental condensation study of vertical superhydrophobic surfaces assisted by hydrophilic constructal-like patterns, International Journal of Thermal Sciences, 135, pp.319–330.
[24] Derby, M.M. Chatterjee, A., Peles, Y. and Jensen, M.K., 2014. Flow condensation heat transfer enhancement in a mini-channel with hydrophobic and hydrophilic patterns, Int. J. Heat Mass Trans., 68, pp.151–160.
[25] Chatterjee, A., Derby, M.M. Peles, Y. and Jensen, M.K., 2013. Condensation heat transfer on patterned surfaces, Int. J. Heat Mass Trans., 66, pp.889–897.
[26] Chatterjee, A., Derby, M.M., Peles, Y., and Jensen, M.K., 2014. Enhancement of condensation heat transfer with patterned surfaces, Int. J. Heat Mass Trans., 71, pp.675– 681.
[27] Davar, H., Nouri, N.M. and Navidbakhsh, M., 2021. Effects of Superhydrophobic, Hydrophobic and Hybrid Surfaces in Condensation Heat Transfer, Journal of Applied Fluid Mechanics, 14(4), pp.1077-1090.
[28] Davar, H., Nouri, N.M., Navidbakhsh, M., Sekhavat, S. and Ansari, A., 2021. Enhancement of dropwise condensation heat transfer on hydrophilic-hydrophobic hybrid surface using microparticles, Experimental Heat Transfer, 35(4), pp.535-552.
[29] ISO Guide to the Expression of Uncertainty in Measurement, 1995.
[30] Lemmon, E.W., Huber, M.L., and McLinden, M.O., 2013. NIST Standard Reference Database 23: Reference Fluid Thermodynamic and Transport Properties-REFPROP, Version 9.1.
[31] Bergman, T.L., Lavine, A.S., Incropera, F.P. and Dewitt, D.P., 2011. Fundamentals of Heat and Mass Transfer.