This work aims to investigate experimentally the effects of corrugation angle, number of fins per inch and velocity on the heat transfer and friction of fin-and-tube heat exchangers. To accomplish this study, six coils (fm-and-tube heat exchangers) with . the same geometry were constructed, four coils with 4FPI (fin per inch) but with different corrugation angles (0°,15°,30° and 45°) besides two coils with corrugation angle 15° but with different nurnber of fins per inch (6 and 8 FPI). The heat transfer characteristics of the six coils were measured in a wind tunnel. The experimental results indicated that the corrugated fins have important effect on the heat transfer and friction. The present work indicated that the augmentation due to corrugated fms
increases with increasing Reynolds number; when the average velocity through heat exchanger increases, both the heat transfer coefficient and the pressure drop increase. If Reynolds number increases, both Colburn factor and friction factor decrease. The
corrugation angle 300 has the highest ratio of heat transfer Colburn factor to the friction factor Gft) followed by angle 15°while the corrugation angle45° has the lowest value of that ratio. The number of fins per inch have an important effect on the heat
transfer characteristics and friction. When the number of fins per inch increases, both the heat transfer and friction increase. Correlations between dependent and independent variables were presented. Comparison between the present and previously
published results is in good agreement.
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