Browse > Article
http://dx.doi.org/10.3795/KSME-B.2017.41.2.079

A Numerical Study on Heat Transfer and Flow Characteristics of a Finned Downhole Coaxial Heat Exchanger  

Park, Chun Dong (Korea Institute of Energy Research)
Lee, Dong Hyun (Korea Institute of Energy Research)
Park, Byung-Sik (Korea Institute of Energy Research)
Choi, Jaejoon (Korea Institute of Energy Research)
Publication Information
Transactions of the Korean Society of Mechanical Engineers B / v.41, no.2, 2017 , pp. 79-86 More about this Journal
Abstract
In this study, the flow and heat transfer characteristics of the finned annular passage were investigated numerically. The annular passage simulates co-axial geothermal heat exchanger, and fins are installed on its inner wall to reduce heat loss from the production passage (annulus) to injection passage (inner pipe). A commercial CFD program, Ansys Fluent, was used with SST $k-{\omega}$ turbulence model. The effects of the geometric parameters of the fin on the inner tube were analyzed under the periodic boundary condition. The result indicated that most parameters had a tendency to increase with an increase in the height and angle of the fin. However, it was confirmed that the Nusselt number of the inner tube on the coaxial 15, 5, 0.3 was lower than that of the smooth tube. Additionally, the Nusselt number of the inner tube exhibited a tendency of decreasing with a decrease in the spacing in Coaxial 15, $S_f$, 0.3.
Keywords
Coaxial Heat Exchanger; Finned Tube; Geothermal Energy; Heat Transfer; CFD;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
연도 인용수 순위
1 Hurter, S. and Schellschmidt, R., 2003, "Atlas of Geothermal Resources in Europe," Geothermics, Vol. 32, Issues 4-6, pp. 779-787.   DOI
2 Morita, K., Matsubayashi, O. and Kusunoki, K., 1985, "Down-Hole Coaxial Heat Exchanger Using Insulated Inner Pipe for Maximum Heat Extraction," Geothermal Resources Council Trans, Vol. 9, PART 1, pp. 45-50.
3 Cho, H. G., Youn, B. and Kim, J. H., 2012, "Analysis of Concentric Heat Exchanger Performance for the Fin Shape on the Inner Tube," Proc. of the SAREK 2012 Summer Annual Meeting, pp. 14-17.
4 Shin, Y. H., Jeong, H. D., Lee, H. H., Chung, H. S. and Jeong, H. M., 2011, "A Numerical Study of Heat Transfer and Flow Characteristics in Shell and Tube Heat Exchanger," Proc. of the SAREK 2011 Summer Annual Meeting, pp. 1070-1073.
5 Lee, K. J., Kwon, O. K., Kim, Y. C. and Seol, W. S., 2012, "An Experimental Study on the Evaporation Heat Transfer Characteristics of Double Pipe Heat Exchanger," Proc. of the KSME 2012 Fall Annual Meeting, pp. 828-832.
6 Park, S. H., Kim, S. K. and Ha, M. Y., 2013, "Numerical Study on Flow and Heat Transfer Characteristics of Pipes with Various Shapes," Trans. Korean Soc. Mech. Eng. B, Vol. 37, No. 11, pp. 999-1007.   DOI
7 Yuan, Z. X., Zhao, L. H. and Zhang, B. D., 2007, "Fin Angle Effect on Turbulent Heat Transfer in Parallel-plate Channel with Flow-inclining Fins," International Journal of Numerical Methods for Heat&Fluid Flow, Vol. 17, No. 1, pp. 5-19.   DOI
8 Ahn, S. W., 2003, "Experimental Studies on Heat Transfer in the Annuli with Corrugated Inner Tubes," Jounal of Mechanical Science and Technology, Vol. 17, No. 8, pp. 1226-1233.
9 Hatami, M., Jafaryar, M., Ganji, D. D. and Gorji-Bandpy, M., 2014, "Optimization of Finned- Tube Heat Exchangers for Diesel Exhaust Waste Heat Recovery Using CFD and CCD Techniques," International Communications in Heat and Mass Transfer, Vol. 57, pp. 254-263.   DOI
10 Incropera, F. P. and DeWitt, D. P., 2001, "Fundamentals of Heat and Mass Transfer," 5th ed, John Wiley & Sons, New York.
11 Meter, F. R., 1994, "Two-Equation Eddy-Viscosity Turbulence Models for Engineering Applications," AIAA Journal, Vol. 32, No. 8, pp. 269-289.
12 Terekhow, V. I., Yarygina, N. I. and Zhdanov, R. F., 2003, "Heat Transfer in Turbulent Separated Flows in the Presence of High Free-Stream Turbulence," International Journal of Heat and Mass Transfer, Vol. 46, pp. 4535-4551.   DOI