Iranian Chemical Engineering Journal

Iranian Chemical Engineering Journal

Investigating the Effect of Cross-Section on the Performance of Conical Coiled Tube Heat Exchangers by Computational Fluid Dynamics

Document Type : Original Article

Authors
1 M. Sc. Student of Chemical Engineering, University of Kurdistan
2 Associate Professor of Chemical Engineering, University of Kurdistan
Abstract
It is significant to determine the optimal dimensions of the heat exchangers to reduce energy consumption. The helical tube heat exchanger is widely used in industry due to its advantages over other types. Therefore, investigating this type of heat exchanger can be an interesting topic. In this research, conical coil tubes with circular, elliptical, and square cross-sections with 10, 30, and 50° cone angles and 15, 30, and 45 mm pitch were modeled by computational fluid dynamics to evaluate the thermal-hydrodynamic performance. The data relating to the Nusselt number and friction factor for all investigated geometric shapes were compared and analyzed. The results showed that the elliptical cross-section tubes have better heat transfer performance compared to other geometries. The results showed that the elliptical cross-section has a better heat transfer performance compared to the square and circular cross-sections by 34.33% and 0.38%, respectively. Moreover, the lower values of the Nusselt number and the friction factor were obtained for the square cross-section due to the change in the thickness of the boundary layer.
Keywords
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[1]        Vivekanandan, M., Saravanan, G., Vijayan, V., Gopalakrishnan, K., & Krishna, J. P. (2021). Experimental and CFD investigation of spiral tube heat exchanger. Materials Today: Proceedings, 37: 3689-3696.‏
[2]        Sivalakshmi, S., Raja, M., & Gowtham, G. (2021). Effect of helical fins on the performance of a double pipe heat exchanger. Materials Today: Proceedings, 43: 1128-1131.‏
[3]        Xu, P., Zhou, T., Xing, J., Chen, J., & Fu, Z. (2022). Numerical investigation of heat-transfer enhancement in helically coiled spiral grooved tube heat exchanger. Progress in Nuclear Energy, 145: 104132.‏
[4]        Jayakumar, J. S., Mahajani, S. M., Mandal, J. C., Iyer, K. N., & Vijayan, P. K. (2010). CFD analysis of single-phase flows inside helically coiled tubes. Computers & chemical engineering, 34(4): 430-446.‏
[5]        Jayakumar, J. S., Mahajani, S. M., Mandal, J. C., Vijayan, P. K., & Bhoi, R. (2008). Experimental and CFD estimation of heat transfer in helically coiled heat exchangers. Chemical engineering research and design, 86(3): 221-232.‏
[6]        Salimpour, M. R. (2009). Heat transfer coefficients of shell and coiled tube heat exchangers. Experimental thermal and fluid science, 33(2): 203-207.‏
[7]        Jamshidi, N., Farhadi, M., Ganji, D. D., & Sedighi, K. (2013). Experimental analysis of heat transfer enhancement in shell and helical tube heat exchangers. Applied thermal engineering, 51(1-2): 644-652.‏
[8]        Yang, G., & Ebadian, M. A. (1996). Turbulent forced convection in a helicoidal pipe with substantial pitch. International Journal of Heat and Mass Transfer, 39(10): 2015-2022.‏
[9]        Eustice, J. (1911). Experiments on stream-line motion in curved pipes. Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character, 85(576): 119-131.‏
[10]     White, C. M. (1929). Streamline flow through curved pipes. Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character, 123(792): 645-663.‏
[11]     Mori, Y., & Nakayama, W. (1967). Study on forced convective heat transfer in curved pipes:(3rd report, theoretical analysis under the condition of uniform wall temperature and practical formulae). International journal of heat and mass transfer, 10(5): 681-695.‏
[12]     Lyne, W. H. (1971). Unsteady viscous flow in a curved pipe. Journal of Fluid Mechanics, 45(1): 13-31.‏
[13]     Dravid, A. N., Smith, K. A., Merrill, E. W., & Brian, P. L. T. (1971). Effect of secondary fluid motion on laminar flow heat transfer in helically coiled tubes. AIChE Journal, 17(5): 1114-1122.‏
[14]     Verma, P. D. S., & Ram, P. (1993). On the
low-Reynolds number magnetic fluid flow in a helical pipe. International journal of engineering science, 31(2), 229-239.‏
[15]     Rennie, T. J., & Raghavan, G. S. V. (2002, July). Laminar parallel flow in a tube-in-tube helical heat exchanger. In AIC2002 Meeting CSAE/SCGR Program, Saskatchwan
(pp. 14-17).‏
[16]     Sieres, J., & Fernández-Seara, J. (2007). Modeling of simultaneous heat and mass transfer processes in ammonia–water absorption systems from general correlations. Heat and mass transfer, 44: 113-123.‏
[17]     Han, J. T., Lin, C. X., & Ebadian, M. A. (2005). Condensation heat transfer and pressure drop characteristics of R-134a in an annular helical pipe. International communications in heat and mass transfer, 32(10): 1307-1316.‏
[18]     Rennie, T. J., & Raghavan, V. G. (2005). Experimental studies of a double-pipe helical heat exchanger. Experimental Thermal and Fluid Science, 29(8): 919-924.‏
[19]     Ali, M., Rad, M. M., Nuhait, A., Almuzaiqer, R., Alimoradi, A., & Tlili, I. (2020). New equations for Nusselt number and friction factor of the annulus side of the conically coiled tubes in tube heat exchangers. Applied Thermal Engineering, 164: 114545.‏