EXPERIMENTAL CORRELATION OF THE CONVECTIVE HEAT TRANSFER COEFFICIENT FOR PV MODULE SURFACES
DOI:
https://doi.org/10.59277/RRST-EE.2026.2.23Keywords:
Correlation, Convective heat transfer coefficient, Photovoltaic (PV) module, Particle swarm optimization (PSO), Least squares methodAbstract
In this paper, a correlation for the convective heat transfer coefficient from the surfaces of photovoltaic (PV) modules is proposed. This correlation was established by experimentally measuring the temperature of PV modules under outdoor conditions, specifically using an open rack-mount setup in which the modules are placed on a freestanding frame and exposed to the surrounding environment. The coefficients of the assumed power-law correlation between the convective heat transfer coefficient and the magnitude of the local wind velocity are determined using the particle swarm optimization (PSO) algorithm and the least-squares method, and the results are compared with measured PV module temperatures calculated using a transient thermal model. Finally, the proposed correlation is compared with similar correlations of this type. While some correlations for the convective heat transfer coefficient yield an average difference of nearly 10 °C between the calculated and measured temperatures of the PV module, the proposed correlation allows the PV module's temperature to be estimated with a deviation of no more than 3 °C.
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