The paper deals with the analytical and experimental determination of the forced convection heat transfer coefficients over the flat coil module. In the analytical part, the forced convection coefficients at different wind speeds are calculated based on various known equations of the forced convection heat transfer coefficient with unheated starting length. The experimental part presents the description of the test: loading the coil with DC current and measurements of the coil temperatures with thermal sensors while it was inside a wind tunnel. Based on the measurement, the convection coefficients were determined. In the final part, the experimental and analytical results are compared. It is found that the accuracy of the analytical results is more precise in highly turbulent flows.
If the inline PDF is not rendering correctly, you can download the PDF file here.
 P. S. Ghahfarokhi A. Kallaste A. Belahcen T. Vaimann and A. Rassolkin “Determination of Forced Convection Coefficient Over a Flat Side of Coil” in 58th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON) 2017 pp. 1–4. https://doi.org/10.1109/RTUCON.2017.8124759
 H.-T. Chen S.-T. Lai and L.-Y. Haung “Investigation of heat transfer characteristics in plate-fin heat sink” Appl. Therm. Eng. vol. 50 no. 1 pp. 352–360 Jan. 2013. https://doi.org/10.1016/j.applthermaleng.2012.08.040
 P. S. Ghahfarokhi A. Kallaste A. Belahcen and T. Vaimann “Thermal analysis of electromagnetic levitation coil” in 17th International Scientific Conference on Electric Power Engineering (EPE) 2016 pp. 1–5. https://doi.org/10.1109/EPE.2016.7521725
 P. S. Ghahfarokhi A. Kallaste A. Belahcen T. Vaimann and A. Rassolkin “Review of thermal analysis of permanent magnet assisted synchronous reluctance machines” in 2016 Electric Power Quality and Supply Reliability (PQ) 2016 pp. 219–224. https://doi.org/10.1109/PQ.2016.7724116
 F. P. Incropera D. P. DeWitt T. L. Bergman and A. S. Lavine Fundamentals of Heat and Mass Transfer 2007.
 M. Rosu et al. Multiphysics Simulation by Design for Electrical Machines Power Electronics and Drives 1st ed. Wiley-IEEE Press 2017. https://doi.org/10.1002/9781119103462
 Y. A. Cengel Heat Transfer: A Practical Approach. New York : McGraw-Hill 2004.
 D. A. Staton and A. Cavagnino “Convection Heat Transfer and Flow Calculations Suitable for Electric Machines Thermal Models” IEEE Trans. Ind. Electron. vol. 55 no. 10 pp. 3509–3516 Oct. 2008. https://doi.org/10.1109/TIE.2008.922604
 E. Sartori “Convection coefficient equations for forced air flow over flat surfaces” Sol. Energy vol. 80 no. 9 pp. 1063–1071 2006. https://doi.org/10.1016/j.solener.2005.11.001
 F. Kreith and D. Goswami Eds. The CRC Handbook of Mechanical Engineering Second Edition. CRC Press 2004.
 P. S. Ghahfarokhi A. Kallaste T. Vaimann and A. Belahcen “Natural convection from flat side’s of coil system” in 2018 19th International Scientific Conference on Electric Power Engineering (EPE) May 2018 pp. 1–5. https://doi.org/10.1109/EPE.2018.8395967
 P. S. Ghahfarokhi A. Kallaste T. Vaimann A. Rassolkin and A. Belahcen “Determination of natural convection heat transfer coefficient over the fin side of a coil system” Int. J. Heat Mass Transf. vol. 126 Part A pp. 677–682 Nov. 2018. https://doi.org/10.1016/j.ijheatmasstransfer.2018.05.071
 M. Markovic L. Saunders and Y. Perriard “Determination of the Thermal Convection Coefficient for a Small Electric Motor” in Conference Record of the 2006 IEEE Industry Applications Conference Forty-First IAS Annual Meeting pp. 58–61 2006. https://doi.org/10.1109/IAS.2006.256520
 O. Meksi and A. O. Vargas “Numerical and experimental determination of external heat transfer coefficient in small TENV electric machines” in 2015 IEEE Energy Conversion Congress and Exposition (ECCE) 2015 pp. 2742–2749. https://doi.org/10.1109/ECCE.2015.7310044
 P. S. Ghahfarokhi A. Kallaste T. Vaimann A. Rassolkin and A. Belahcen “Determination of Thermal Convection Coefficient from Coil’s Flat Plate Side” in 2017 IEEE 58th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON) Riga Latvia 2017.
 M. Ahmadi G. Mostafavi and M. Bahrami “Natural convection from rectangular interrupted fins” Int. J. Therm. Sci. vol. 82 pp. 62–71 2014. https://doi.org/10.1016/j.ijthermalsci.2014.03.016
 H. G. C. Woo J. A. Peterka J. E. Cemak “Wind Tunnel Measurements in the Wakes of Structures” Fort Collins CO United States 1977.
 S. M. Ghiaasiaan Convective Heat and Mass Transfer. Cambridge University Press 2011.