Free Convection from a One End Closed Vertical Pipe with Annular Fins: A Computational Study

Document Type : Research Paper

Authors

1 Department of Mechanical Engineering, C. V. Raman Global University, Odisha, India

2 Mechanical Engineering, National Institute of Technology, Rourkela, Odisha, India

Abstract

Cylindrical objects in heat transfer applications have always taken the spotlight due to their compact nature and better surface area-to-volume ratio over their cuboid counterparts. Despite this advantage, fins have been used to enhance the heat transfer properties of such geometries. This study involves one such geometry where the top of the cylinder is open to the surrounding atmosphere and the cylinder is fitted with annular fins of different sizes and spacing. The k-ε model is used to simulate the turbulent cases along with a density-based solver. The cylinder is modeled to be a heat source with a constant temperature of 350 K and the surrounding atmosphere being air at 300 K. Nusselt number and effectiveness of the fins were calculated and analyzed. The heat flow rate experienced a maximum increase of 50% when the number of fins is raised from S/d 0.9 to S/d 0.3. The maximum effectiveness occurs at Ra = 1011, with a value of 4.44 observed for S/d of 0.3 and d/D of 0.25. The maximum values for effectiveness are observed at lower d/D and S/d values.

Keywords

Main Subjects

[1]          B. K. Rana, Numerical investigation on free convection from an isothermally heated hollow inclined cylinder suspended in air, Numerical Heat Transfer, Part A: Applications, Vol. 83, No. 11, pp. 1195-1219, 2023/06/03, 2023.
[2]          S. Mohamad, S. K. Rout, J. R. Senapati, S. K. Sarangi, Entropy formation due to conjugate natural convection in a cylindrical open cavity under isothermal boundary condition at inner wall, Journal of Thermal Analysis and Calorimetry, Vol. 148, No. 24, pp. 13913-13927, 2023/12/01, 2023.
[3]          S. Mohamad, S. K. Rout, J. R. Senapati, S. K. Sarangi, Numerical Investigation of Conjugate Natural Convection From a Vertical Cylindrical Open Cavity, ASME Journal of Heat and Mass Transfer, Vol. 145, No. 8, 2023.
[4]          B. K. Rana, J. R. Senapati, Natural Convection From an Isothermally Heated Hollow Vertical Cylinder Submerged in Quiescent Power-Law Fluids, Journal of Thermal Science and Engineering Applications, Vol. 15, No. 2, 2022.
[5]          A. Mukherjee, V. Chandrakar, J. R. Senapati, Thermo-fluid characteristics of an IRS system with louvered cylindrical diathermic funnels considering surface radiation: A three-dimensional numerical exercise, International Communications in Heat and Mass Transfer, Vol. 135, pp. 106132, 2022/06/01/, 2022.
[6]          S. Mohamad, S. K. Rout, J. R. Senapati, S. K. Sarangi, Entropy generation analysis and cooling time estimation of a blast furnace in natural convection environment, Numerical Heat Transfer, Part A: Applications, Vol. 82, No. 10, pp. 666-681, 2022/11/17, 2022.
[7]          B. K. Rana, B. Singh, J. R. Senapati, Thermofluid Characteristics on Natural and Mixed Convection Heat Transfer From a Vertical Rotating Hollow Cylinder Immersed in Air: A Numerical Exercise, Journal of Heat Transfer, Vol. 143, No. 2, 2020.
[8]          M. K. Dash, S. K. Dash, Natural convection heat transfer and fluid flow around a thick hollow vertical cylinder suspended in air: A numerical approach, International Journal of Thermal Sciences, Vol. 152, pp. 106312, 2020/06/01/, 2020.
[9]          M. K. Dash, S. K. Dash, A Comparative Numerical Study on Conjugate Natural Convection From Vertical Hollow Cylinder With Finite Thickness Placed on Ground and in Air, Journal of Thermal Science and Engineering Applications, Vol. 13, No. 2, 2020.
[10]        J. Liu, H. Liu, Q. Zhen, W.-Q. Lu, Laminar natural convection heat transfer from a pair of attached horizontal cylinders set in a vertical array, Applied Thermal Engineering, Vol. 115, pp. 1004-1019, 2017/03/25/, 2017.
[11]        A. Shah, B. K. Rana, Numerical investigation of free convection around a pair of vertically-aligned isothermally-heated vertical hollow cylinders, Numerical Heat Transfer, Part A: Applications, pp. 1-24.
[12]        H.-T. Chen, W.-X. Ma, P.-Y. Lin, Natural convection of plate finned tube heat exchangers with two horizontal tubes in a chimney: Experimental and numerical study, International Journal of Heat and Mass Transfer, Vol. 147, pp. 118948, 2020/02/01/, 2020.
[13]        S.-C. Wong, W.-Y. Lee, Numerical study on the natural convection from horizontal finned tubes with small and large fin temperature variations, International Journal of Thermal Sciences, Vol. 138, pp. 116-123, 2019/04/01/, 2019.
[14]        J. Vogel, M. Johnson, Natural convection during melting in vertical finned tube latent thermal energy storage systems, Applied Energy, Vol. 246, pp. 38-52, 2019/07/15/, 2019.
[15]        S. Acharya, S. K. Dash, Natural convection heat transfer from a horizontal hollow cylinder with internal longitudinal fins, International Journal of Thermal Sciences, Vol. 134, pp. 40-53, 2018/12/01/, 2018.
[16]        J. R. Senapati, S. K. Dash, S. Roy, Numerical investigation of natural convection heat transfer from vertical cylinder with annular fins, International Journal of Thermal Sciences, Vol. 111, pp. 146-159, 2017/01/01/, 2017.
[17]        Q. Shen, D. Sun, Y. Xu, T. Jin, X. Zhao, N. Zhang, K. Wu, Z. Huang, Natural convection heat transfer along vertical cylinder heat sinks with longitudinal fins, International Journal of Thermal Sciences, Vol. 100, pp. 457-464, 2016/02/01/, 2016.
[18]        J. R. Senapati, S. K. Dash, S. Roy, Numerical investigation of natural convection heat transfer over annular finned horizontal cylinder, International Journal of Heat and Mass Transfer, Vol. 96, pp. 330-345, 2016/05/01/, 2016.
[19]        A. Kumar, J. B. Joshi, A. K. Nayak, P. K. Vijayan, 3D CFD simulations of air cooled condenser-II: Natural draft around a single finned tube kept in a small chimney, International Journal of Heat and Mass Transfer, Vol. 92, pp. 507-522, 2016/01/01/, 2016.
[20]        Y. Joo, S. J. Kim, Thermal optimization of vertically oriented, internally finned tubes in natural convection, International Journal of Heat and Mass Transfer, Vol. 93, pp. 991-999, 2016/02/01/, 2016.
[21]        B. Li, C. Byon, Experimental and numerical study on the heat sink with radial fins and a concentric ring subject to natural convection, Applied Thermal Engineering, Vol. 90, pp. 345-351, 2015/11/05/, 2015.
[22]        M. J. Hosseini, A. A. Ranjbar, M. Rahimi, R. Bahrampoury, Experimental and numerical evaluation of longitudinally finned latent heat thermal storage systems, Energy and Buildings, Vol. 99, pp. 263-272, 2015/07/15/, 2015.
[23]        D.-K. Kim, Comparison of optimal thermal performances of finned tube annuli with various fin shapes, International Journal of Heat and Mass Transfer, Vol. 175, pp. 121402, 2021/08/01/, 2021.
[24]        D. Kim, D.-K. Kim, Experimental study of natural convection from vertical cylinders with branched pin fins, International Journal of Heat and Mass Transfer, Vol. 177, pp. 121545, 2021/10/01/, 2021.
[25]        J. R. Senapati, S. K. Dash, S. Roy, 3D numerical study of the effect of eccentricity on heat transfer characteristics over horizontal cylinder fitted with annular fins, International Journal of Thermal Sciences, Vol. 108, pp. 28-39, 2016/10/01/, 2016.
[26]        K. T. Park, H. J. Kim, D.-K. Kim, Experimental study of natural convection from vertical cylinders with branched fins, Experimental Thermal and Fluid Science, Vol. 54, pp. 29-37, 2014/04/01/, 2014.
[27]        P. Singh, A. K. Patil, Experimental investigation of heat transfer enhancement through embossed fin heat sink under natural convection, Experimental Thermal and Fluid Science, Vol. 61, pp. 24-33, 2015/02/01/, 2015.
[28]        B. Singh, S. K. Dash, Natural convection heat transfer from a finned sphere, International Journal of Heat and Mass Transfer, Vol. 81, pp. 305-324, 2015/02/01/, 2015.
[29]        K. T. Park, J. W. Lee, M. G. Lee, H. J. Kim, D.-K. Kim, Nusselt number correlation for vibration-assisted convection from vertically oriented plate fins, International Journal of Heat and Mass Transfer, Vol. 78, pp. 522-526, 2014/11/01/, 2014.
[30]        Y. Liu, C. Lei, J. C. Patterson, Natural convection in a differentially heated cavity with two horizontal adiabatic fins on the sidewalls, International Journal of Heat and Mass Transfer, Vol. 72, pp. 23-36, 2014/05/01/, 2014.
[31]        G.-J. Huang, S.-C. Wong, C.-P. Lin, Enhancement of natural convection heat transfer from horizontal rectangular fin arrays with perforations in fin base, International Journal of Thermal Sciences, Vol. 84, pp. 164-174, 2014/10/01/, 2014.
[32]        W. H. McAdams, Heat transmission, (No Title), 1954.
[33]        E. R. G. Eckert, T. W. Jackson, Analysis of turbulent free-convection boundary layer on flat plate,  pp. 1950.
Volume 55, Issue 4
October 2024
Pages 589-604
  • Receive Date: 15 March 2024
  • Revise Date: 30 March 2024
  • Accept Date: 01 April 2024