| Summary: | Star-shaped fins are a newer type of fin for which correlations for heat transfer and pressure drop do not yet exist in the literature. Therefore, correlation equations for air-side heat transfer and pressure drop in a finned heat exchanger with star-shaped stainless-steel fins in staggered arrangement were developed in this work. To obtain these correlations, a numerical analysis of the basic heat exchanger geometry and another 21 variants of heat exchanger geometry was performed using computational fluid dynamics, and then the results of laboratory tests of a model of heat exchangers with star-shaped fins were used. In the numerical analysis, the fin pitch, the fin thickness, and the air velocity at the inlet to the heat exchanger were varied. The Nusselt (<i>Nu</i>) and Euler (<i>Eu</i>) numbers were determined for each variation analyzed. Initial correlations for <i>Nu</i> and <i>Eu</i> were derived using the least-squares deviation method. The correlation coefficients thus obtained were adjusted to agree with the results of the laboratory tests. The deviation of the final obtained correlation for <i>Nu</i> from the experimental test results was up to 10% in the range of <i>Re</i> < 3500, whereas for higher values of <i>Re</i>, the deviation was less than 2%. The <i>Eu</i> correlation deviated from experimental results up to 19% in the range of <i>Re</i> < 4000, whereas in the range of <i>Re</i> > 5600, the deviation was less than 1%. The correlations were valid in the range 2000 < <i>Re</i> < 16,000.
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