Numerical study to predict optimal configuration of fin and tube compact heat exchanger with various tube shapes and spatial arrangements

The study aims at numerically evaluating the thermal hydraulic performance of fin tube heat exchangers with circular, oval and flat tubes having inline and staggered arrangement. Three performance evaluation criteria (PECs), namely, area goodness factor (PEC1), heat transfer rate per unit fan power consumption (PEC2) and heat transfer rate per unit total power consumption (PEC3) are considered. Furthermore, the MOORA (multi-objective optimization on the basis of ratio analysis) method is employed to obtain the order of performance and that order is compared with the conventional PECs (performance evaluation criteria), showing good agreements. From the overall optimization study finally, it has been observed that the oval tube having highest axes ratio is the optimum configuration based on the considered PECs. It shows an increase in heat transfer coefficient by 13.99% at lower airside Reynolds number of (Re = 400) and 4.99% at higher airside Reynolds number (Re = 900). Also, the pressure drop is reduced by 39.94% at higher Reynolds number (Re = 900) compared to the circular tube shape with the inline arrangement.