University of Technology-Iraq, Alsina’a street, 10066 Baghdad, Iraq.


Thermal regulation has now become a staple in the design of electronic devices. As a result of technological advances in the electronic industry, component miniaturization and thermal system management are becoming more and more important. Due to the high demand for device performance and the need for better thermal management, this paper present a detailed theoretical review of heat transfer by conventional methods in electronic devices and equipment such as air cooling, water cooling, etc. to provide an ideal framework for a practical application in electronic cooling. With reference to the possibility of investing unconventional ways to reduce the energy consumed in the cooling process and preserving the environment through the possibility of replacing solid circuit boards with flexible circuits and studying their properties in improving heat transfer and deformation of P.C.B using the interaction of fluid structure under thermal and flow effects.


  • Provide a detailed review of heat transfer methods in electronic devices.
  • New environmentally friendly technologies are reviewed to improve heat transfer.
  • Discussing the possibility of replacing RPCB with FPCB in electronic circuits.
  • FPCB investment discussion to improve PCB thermal design.


Main Subjects

[1] L. T. Yeh, Review of heat transfer technologies in electronic equipment, J. of electron, 117 (1995) 333-339.
[2] H. Y. Zhang, Y. C., Mui, and M. Tarin, M.  Analysis of thermoelectric cooler performance for high power electronic packages. Applied thermal engineering, 30 (2010) 561-568.
[3] J. Holman, Heat transfer tenth edition. The McGraw-Hill Companies. U.S.A. 2010
[4] S., Kumar, and A. Tariq.  Steady state experimental investigation of thermal contact conductance between curvilinear contacts using liquid crystal thermography. International Journal of Thermal Sciences, 118 (2017) 53-68.
[5] Y., Xian, P. Zhang, S. Zhai, P. Yuan, and D. Yang. Experimental characterization methods for thermal contact resistance: A review. Applied Thermal Engineering, 130 (2018) 1530-1548.
[6] Y. Jeng, J. Chen, and C. Cheng. Theoretical and experimental study of a thermal contact conductance model for elastic, elastoplastic and plastic deformation of rough surfaces. Tribology Lett; 14:251e9, 2003.
[7] C. V.  Madhusudana. Thermal conductance of cylindrical joints. International Journal of Heat and Mass Transfer, 42 (1999) 1273-1287.
[8] J. M. Jalil. & S. J.  Habeeb, Mixed Convection from Electronic Equipment Component at Different Position at Enclosure by Primitive Variables Method. Journal of Engineering, 12 (2006).
[9] B.Sarper, M. Saglam. & O.Aydin. Experimental and numerical investigation of natural convection in a discretely heated vertical channel: Effect of the blockage ratio of the heat sources. International Journal of Heat and Mass Transfer, 126, 894-910, 2018.
[10] A.Dogan, M. Sivrioglu, and S. Baskaya, Investigation of mixed convection heat transfer in a horizontal channel with discrete heat sources at the top and at the bottom. International Journal of Heat and Mass Transfer, 49 (2006) 2652-2662.
[11] H.Laouira, F. Mebarek‐Oudina, Hussein, A. K., Kolsi, L., Merah, A., & Younis, O. Heat transfer inside a horizontal channel with an open trapezoidal enclosure subjected to a heat source of different lengths. Heat Transfer—Asian Research, 49(2020) 406-423.
[12] S.Durgam, S. P. Venkateshan, and T. Sundararajan, Experimental and numerical investigations on optimal distribution of heat source array under natural and forced convection in a horizontal channel. International Journal of Thermal Sciences, 115 (2017) 125-138.
[13] M.Shim, M. Y.Ha, and J. K.  Min. A numerical study of the mixed convection around slanted-pin fins on a hot plate in vertical and inclined channels. International Communications in Heat and Mass Transfer, 118 (2020) 104878.
[14] A. M. Anderson, and R. J. Moffat. Direct air cooling of electronic components: reducing component temperatures by controlled thermal mixing: J. of Heat Transfer, 113 (1991) 56-62.
[15] I. Y.Hussain and H. S. Abdulla. Optimization of Thermal Layout Design of Electronic Equipment's on the Printed Circuit Board. Journal of Engineering, 12 (2006).
[16] B. Sarper, M. Saglam and O.Aydin. Experimental and numerical investigation of natural convection in a discretely heated vertical channel: Effect of the blockage ratio of the heat sources. International Journal of Heat and Mass Transfer, 126 (2018) 894-910.
[17] R.Grimes, M.Davies, J. Punch, and T. Dalton, & R. Cole. Modeling electronic cooling axial fan flows. J. Electron. Packag. 123(2001) 112-119.
[18] J. M. Jalil. Numerical and Experimental Study of Cooling in Desktop Computer with Block Heat Sink. Engineering and Technology Journal, 36 (2018).
[19] O. Manca, S. Nardini, K. Khanafer, K. Vafai. Effect of heated wall position on mixed convection in a channel with an open cavity. Num Heat Transfer A.; 43(2003) 259‐282.
[20] V. Cardenas, C. Trevino, I. Rosas, L. Martinez‐Suastegui. Experimental study of buoyancy and inclination effects on transient mixed convection heat transfer in a channel with two symmetric open cubic cavities with prescribed heat flux. Int J Therm Sci ;140: (2019) 71‐86.
[21] R.Lucchese, D. Varagnolo, and A. Johansson. Controlled Direct Liquid Cooling of Data Servers. IEEE Transactions on Control Systems Technology, 2020.
[22] G. Liang, and  I. Mudawar. Review of pool boiling enhancement by surface modification. International Journal of Heat and Mass Transfer, 128 (2019) 892-933.
[23] Lee, M.  Mahalingam, and P.J.C. Normington. Subcooled pool boiling critical heat flux in dielectric liquid mixtures: (1993)134-137.
[24] Q. Jin, J. T., and   Wen, S. Narayanan. Dynamic control of pressure drop oscillation in a microchannel cooling system. Heat Transfer Engineering, (2020)1-16.
[25] A. A.Imran, N. S. Mahmoud, and H. M.  Jaffar. Numerical and experimental investigation of heat transfer in liquid cooling serpentine mini-channel heat sink with different new configuration models. Thermal Science and Engineering Progress, 6 (2018) 128-139.
[26] W. W.Wits, T. H. Vaneker, J. H. Mannak, and R. Legtenberg. Novel cooling strategy for electronic packages: Directly injected cooling. C.I.R.P. journal of manufacturing science and technology, 1(2009) 142-147.
[27] P.Naphon, and S. Wongwises. Investigation on the jet liquid impingement heat transfer for the central processing unit of personal computers. International Communications in Heat and Mass Transfer, 37 (2010) 822-826.
[28] B. Abdullahi, & R. K. Al-dadah. Thermosyphon heat pipe technology. In Recent Advances in Heat Pipes. Intech Open., 2019.
[29] W. Wits, R. Legtenberg, J. Mannak, and B.van Zalk, (2006, November). Thermal management through in-board heat pipes manufactured using printed circuit board multilayer technology, Thirty-First IEEE/CPMT International Electronics Manufacturing Technology Symposium (2006) 55-61.
[30] Y. Z.Ling, X. S.Zhang, F. Wang, & X. H. She. Performance study of phase change materials coupled with three-dimensional oscillating heat pipes with different structures for electronic cooling. Renewable Energy, 154 (2020) 636-649.
[31] M.S. Dresselhaus, G. Chen, M.Y. Tang, R.G. Yang, H. Lee, D.Z. Wang, et al., New directions for low-dimensional thermoelectric materials, Adv. Mater. 19 (2007) 1043–1053.
[32] Y. Cai, Y.Wang, D. Liu, and F. Y.  Zhao. Thermoelectric cooling technology applied in the field of electronic devices: Updated review on the parametric investigations and model developments. Applied Thermal Engineering, 148 (2019) 238-255.
[33]   Y. CAI, D.-D. Zhang, D. Liu, F.-Y. Zhao, H.-Q. Wang, Air source thermoelectric heat pump for simultaneous cold air delivery and hot water supply: full modeling and performance evaluation, Renew. Energy 130 (2019) 968–981.
[34] Y. Zhou, T.Zhang, F.Wang, and Y.Yu. Performance analysis of a novel thermoelectric assisted indirect evaporative cooling system. Energy, 162 (2018) 299-308.
[35] A. M.Iqbal, M. S. A.Aziz, M. Z.Abdullah, & M. H. H.  Ishak, (2019, June). Temperature Prediction on Flexible Printed Circuit Board in Reflow Oven Soldering for Motherboard Application. In I.O.P. Conference Series: Materials Science and Engineering 530 (2019) 012019. I.O.P. Publishing.
[36] L. C.Hooi, M. Z.Abdullah, & I. A.  Azid, (2017, March). Numerical simulation of fluid-structure interaction on flexible P.C.B. with multiple ball grid array components. In A.I.P. Conference Proceedings 1818 (2017) 020018. A.I.P. Publishing L.L.C.
[37] C. H.Lim, M. Z.Abdullah, I. A. Azid, and C. Y.  Khor. Heat transfer enhancement by flexible printed circuit board's deformation. International Communications in Heat and Mass Transfer, 84 (2017) 86-93.
[38] C. H.Lim, M. Z. Abdullah, I. A. Azid, C. Y. Khor, M. A. Aziz, and M. H. H.  Ishaik, . Heat transfer and deformation analysis of flexible printed circuit board under thermal and flow effects. Circuit World., 2020.
[39] C. H.Lim, M. Z.Abdullah, I. A. Azid, and C. Y.  Khor. The effect of freestream flow velocities on the flexible printed circuit board with different BGA package arrangements. Arabian Journal for Science and Engineering, 42 (2017) 2075-2086.
[40] Available [Online]., 2021.