This is an unedited manuscript accepted for publication and provided as an Article in Press for early access at the author’s request. The article will undergo copyediting, typesetting, and galley proof review before final publication. Please be aware that errors may be identified during production that could affect the content. All legal disclaimers of the journal apply.
Khushi Gharate,
Srushti Ghadge,
Sujit Gore,
Abhijeet Malge,
Pramod Kothmire,
- UG Scholar, Department of Mechanical Engineering, MITAOE, Alandi Pune, Maharashtra, India
- UG Scholar, Department of Mechanical Engineering, MITAOE, Alandi Pune, Maharashtra, India
- UG Scholar, Department of Mechanical Engineering, MITAOE, Alandi Pune, Maharashtra, India
- Professor, Department of Mechanical Engineering, MITAOE, Alandi Pune, Maharashtra, India
- Associate Professor, Department of Mechanical Engineering, MITAOE, Alandi Pune, Maharashtra, India
Abstract
Metallic materials such as steel and copper have traditionally dominated heat exchanger manufacturing because of their excellent thermal conductivity, mechanical strength, and long-established industrial reliability. However, their high weight, susceptibility to corrosion in aggressive operating environments, and inability to provide tunable thermal properties have motivated interest in alternative materials for next-generation thermal systems. Thermally conductive polymer composites reinforced with graphene nanoplatelets (GNP), boron nitride (BN), and carbon-based fillers offer an attractive solution due to their lightweight nature, corrosion resistance, and controllable thermal conductivity. Nevertheless, their relatively lower thermal conductivity compared to metals remains a critical challenge limiting widespread adoption in compact heat exchangers. This study investigates whether geometric enhancement through multi-pass flow architecture can compensate for reduced wall conductivity and enable practical implementation of polymer composite heat exchanger tubes. A three-dimensional computational fluid dynamics (CFD) model incorporating conjugate heat transfer and the realizable k–ε turbulence model was developed for single-pass, two-pass, and four-pass double-pipe heat exchanger configurations. Numerical predictions were experimentally validated using a fabricated steel multi-pass heat exchanger instrumented with calibrated Type-K thermocouples and rotameters. Experiments were conducted under steady-state conditions with hot fluid entering at 75°C and cold fluid at 25°C at identical inlet velocities of 3 m/s. Good agreement between numerical and experimental results confirmed the reliability of the developed model. Following validation, tube-wall thermal conductivity was systematically varied from 0.2 to 20 W/m·K to represent neat polymers through thermally enhanced polymer composites. The results demonstrate that multi-pass configurations significantly compensate for reduced conductivity effects. A four-pass polymer composite tube with conductivity near 5 W/m·K operated within 9–13% of the steel baseline while simultaneously achieving 40–60% weight reduction and complete corrosion resistance. The findings establish a practical conductivity target of 5–10 W/m·K for lightweight polymer composite heat exchangers intended for compact and corrosion-sensitive thermal applications.
Keywords: CFD simulation, multi-pass double-pipe heat exchanger, Polymer composite tube, Thermal conductivity parametric study, Thermo-hydraulic performance, Lightweight heat exchanger, Sustainable thermal design, Conjugate heat transfer.
References
[1] Pachegaonkar SS, Patil SR, Deshmukh DA. Performance analysis of double pipe heat exchanger with annular twisted tape insert. International Journal of Engineering and Advanced Technology. 2014;3(3):1–6.
[2] Nawale PK, Mule A, Powar S, Kothmire PP. Enhancement technique of heat transfer using inserted twisted tape. Journal of Thermal Engineering. 2021;9:93–99.
[3] Dhumal GS, Jadhav RS, Patil VM, More AB. Enhancing heat transfer performance in a double tube heat exchanger using twisted tape inserts. Case Studies in Thermal Engineering. 2023;42:102756.
[4] El Maakoula A, Laknizi A, Saadeddine S, Meziane M, Ben Abdellah A. Numerical design and investigation of heat transfer enhancement in a double-pipe heat exchanger. Energy Conversion and Management. 2017;133:76–86.
[5] Bhuiyan AA, Islam AKMS. CFD analysis of different fin-and-tube heat exchangers. Proceedings of the 13th Annual Paper Meet of the Institution of Engineers Bangladesh. 2011;1–6.
[6] Hameed VM, Kumar R, Singh AK. Experimental study of turbulent flow heat transfer and pressure loss in a double pipe heat exchanger with triangular fins. International Journal of Energy and Environment. 2015;7:149–158.
[7] Bhola M, Kumar V, Singh S. Heat transfer enhancement in concentric tube heat exchanger in ANSYS Fluent. International Journal of Engineering Research and Technology. 2015;4(4):1–5.
[8] Assaf YH, Hasan AA, Mahmood HM, Kareem RK. Investigation of heat transfer performance in heat exchanger tube equipped with special fixed ring inserts and twisted tape elements. Progress in Mechanical Engineering. 2025;12(1):1–14.
[9] Hasan MA, Rashid FL, Kareem AH. Nanofluid-based enhancement in finned cooling systems. Thermal Engineering and Applications. 2023;18(2):55–68.
[10] Xu Y, Chung DDL, Morrell C. Electrically and thermally conducting composites made from graphite platelets and epoxy resin for use as thermal interface materials. Carbon. 2022;191:247–260.
[11] Chen H, Ginzburg VV, Yang J, Yang Y, Liu W, Huang Y, Du L, Chen B. Thermal conductivity of polymer-based composites: fundamentals and applications. Progress in Polymer Science. 2023;59:41–85.
[12] Burger N, Laachachi A, Ferriol M, Lutz M, Toniazzo V, Ruch D. Review of thermal conductivity in composites: mechanisms, parameters and theory. Progress in Polymer Science. 2022;61:1–28.
[13] Tükenmez E, Yalçın B. Thermal and hydraulic characterization of polymer-based heat exchangers for industrial applications. International Journal of Heat and Mass Transfer. 2021;164:120559.
[14] Khoshvaght-Aliabadi M, Alizadeh M, Khaligh SF. Thermohydraulic performance of corrugated polymer heat exchangers: a review. Renewable and Sustainable Energy Reviews. 2023;182:113384.
[15] Liu Z, Chen Y, Li Y, Zhao X. Thermal conductivity enhancement of epoxy composites via graphene nanoplatelet alignment under electric fields. Composites Part A: Applied Science and Manufacturing. 2023;164:107274.
[16] Wang Y, Shi H, Qian X, Sun R, Zhao C, Zhao Y. Thermal management with boron nitride platelet composites: from fabrication to application in heat exchangers. Journal of Materials Science and Technology. 2024;172:1–18.
[17] Zaheed L, Jachuck RJJ. Review of polymer compact heat exchangers, with special emphasis on a polymer film unit. Applied Thermal Engineering. 2004;24(16):2323–2358.
[18] Mehendale SS. Heat exchanger thermal analysis using polymer tube membranes. Applied Thermal Engineering. 2020;163:114387.
[19] Rao GA, Levy Y. Semi-empirical methodology for performance estimation of double pipe finned heat exchanger. ASME ESDA Conference Proceedings. 2008;1–8.
[20] Shewale OM, Patil BM, Farkade HS. Experimental investigation of double pipe heat exchanger with helical fins. Case Studies in Thermal Engineering. 2015;5:48–58.
[21] Ameen SH, Mahmood DMN. Experimental and numerical investigation for structural and thermal characteristics of externally finned double pipe heat exchanger. International Journal of Application or Innovation in Engineering and Management. 2014;3(4):1–9.
[22] Hussein SAA. Experimental investigation of double pipe heat exchanger using semi-circular disc baffles. Journal of Engineering Research and Applications. 2015;5(7):45–52.
[23] Narayanan NS, Babu KA, Nair PS. Modelling and simulation of helical fluid flow through double start screw type heat exchanger. Thermal Science. 2011;15:183–194.
[24] Kundu B, Das PK, Mitra S. Beneficial design of shell and tube heat exchangers. Engineering Science and Technology. 2015;18:336–350.
[25] Patil AA, Chavan VS, Patil SS. Design, development and testing of double pipe heat exchanger with heat transfer enhancement liners. International Journal of Science Technology Management and Research. 2017;2(1):1–6.
[26] Debtera B, Neme I, Prabhu SV. CFD simulation of a double pipe heat exchanger. International Journal of Scientific Research and Review. 2018;7(12):329–338.
[27] Gadave NM, Kothmire PP. Thermo-hydraulic performance evaluation of shell and tube heat exchanger with different tube geometries. International Journal of Engineering and Technology. 2019;9:2249–8958.
[28] Deshmukh S, Shinde A, Kothmire PP. Experimental study of heat transfer in composite vessels. Proceedings of the Conference on Fluid Mechanics and Fluid Power. 2023;627–640.
[29] Londhe S, Auti V, Kothmire PP, Patil S, Jadhav R. Impact of economiser tube geometry on water heating. Proceedings of the Conference on Fluid Mechanics and Fluid Power. 2023;275–287.
[30] Nagarhalli P, Mayekar A, Pakhare R, Pachkudave T, Bhalerao Y, Kothmire PP. Natural and forced convective heat transfer from finned spheres. Proceedings of the Conference on Fluid Mechanics and Fluid Power. 2023;365–379.
[31] Tajane Y, Lohar P, Ghangar G, Eshi M, Kothmire PP. Experimental and CFD investigation of radiative heat transfer for room cooling. Proceedings of the Conference on Fluid Mechanics and Fluid Power. 2023;337–350.
[32] Damdhar A, Gunturkar S, Dhumal S, Jagtap K, Pathak A, Malkunjikar S, Kothmire PP. CFD analysis of exhaust gas flow through muffler. Proceedings of the Conference on Fluid Mechanics and Fluid Power. 2022;599–613.
[33] Narad V, Malu P, Giri P, Borole S, Naikare A, Kothmire PP. Numerical investigation to study the effective position of air conditioner in an office room. Proceedings of the Conference on Fluid Mechanics and Fluid Power. 2022;209–220.
[34] Pawar A, Halikhede S, Umbarkar A, Kedar A, Waghmode P, Kothmire PP. CFD analysis of different designs of greenhouse. Proceedings of the Conference on Fluid Mechanics and Fluid Power. 2022;277–288.
[35] Powar S, Chitrakar N, Chacharkar L, Adarsh P, Karhale S, Patil R, Kothmire PP. Effect of surface roughness on boundary layer thickness. Proceedings of the Conference on Fluid Mechanics and Fluid Power. 2022;371–380.
[36] Shindge M, Dhamnikar P, Tamboli S, Fulzele R, Gatlewar O, Funde A, Kothmire PP. CFD analysis of catalytic converter to optimize back pressure and velocity. Proceedings of the Conference on Fluid Mechanics and Fluid Power. 2022;289–303.
[37] Yadav P, Kothmire PP. CFD analysis of exhaust pipe of a diesel engine. AIP Conference Proceedings. 2021;2417:060002.
[38] Karlekar O, Barve S, Kothmire PP. Thermo-hydraulic enhancement of annular finned shell-and-tube heat exchangers using epoxy-based polymer composites: A material–geometry coupled CFD investigation. Journal of Polymer & Composites. 2026;14(Special Issue 02):669–684.
[39] Karkal P, Barve S, Kothmire PP. Experimental and CFD investigation of an epoxy-based thermally conductive polymer composite U-tube shell-and-tube heat exchanger. Journal of Polymer & Composites. 2026;14(Special Issue 02):685–700.
[40] Patil R, Kamble S, Kokare P, Goudar M, Kothmire PP. Investigation to enhance performance of finned U-tube shell-and-tube heat exchangers using epoxy based polymer composite. Journal of Polymer & Composites. 2026;14(Special Issue 02):618–633.
[41] Patel A, Gujar S, Bhalerao Y, Kothmire PP. Influence of epoxy-based thermally conductive polymer composites on the thermo-hydraulic performance of finned helical coil heat exchangers. Journal of Polymer & Composites. 2026;14(Special Issue 02):586–602.
[42] Dabhade T, Gawari T, Nawale P, Shah B, Jain S, Kothmire PP. Corrugated tube shell-and-tube heat exchanger using epoxy-based polymer composite coatings for lightweight and efficient thermal systems. Journal of Polymer & Composites. 2026;14(Special Issue 02):603–617.
[43] Dhanawade N, Joshi S, Wankhade P, Bhalerao V, Kothmire PP. Thermal dissipation performance of metal–polymer composite heat exchanger for enhanced thermal management in compact geysers. Journal of Polymer & Composites. 2026;14(Special Issue 02):618–651.
[44] Kapure S, Rathod P, Patil A, Rai H, Kothmire PP. Multiphysics optimization of polymer–metal hybrid electrode geometry in electrostatic precipitators. Journal of Polymer & Composites. 2026;14(Special Issue 02):701–716.
[45] Mankar B, Gopale Y, Balghare S, Jadhav P, Kothmire PP. Thermo-electrical performance enhancement of a lightweight polymer–metal hybrid electrostatic precipitator. Journal of Polymer & Composites. 2026;14(Special Issue 02):652–668.
[46] Dixit S, Londhe K, Patil A, Kanase S, Goudar M, Kothmire PP. Characterization and performance of a multiphase lignocellulosic–polymeric composite growth media in an IoT-automated NFT hydroponic system. Journal of Polymer & Composites. 2026;14(Special Issue 02):542–555.
[47] Guoqing Yi, Luke C Henderson, Jingliang Li, Weiwei Lei, Shuaifei Zhao. Thermally conductive composites as polymer heat exchangers for water and energy recovery: From materials to products. Applied Thermal Engineering. 2025;268: 125845.
Journal of Polymer & Composites
| Volume | 14 | |
| 05 | ||
| Received | 29/04/2026 | |
| Accepted | 04/07/2026 | |
| Published | 23/09/2026 | |
| Publication Time | 147 Days |