Determination of Heat Transfer Coefficient for the Air Forced Cooling Over a Flat Side of Coil

Payam Shams Ghahfarokhi; Ants Kallaste; Anouar Belahcen; Toomas Vaimann

doi:10.2478/ecce-2019-0003

Determination of Heat Transfer Coefficient for the Air Forced Cooling Over a Flat Side of Coil

Authors

Payam Shams Ghahfarokhi Tallinn University of Technology
Ants Kallaste Tallinn University of Technology
Anouar Belahcen Aalto University
Toomas Vaimann Tallinn University of Technology

DOI:

https://doi.org/10.2478/ecce-2019-0003

Keywords:

Flat surface, Forced convection, Heat transfer coefficient, Laminar and turbulent flow

Abstract

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.

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