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Numerical analysis of drag reduction characteristics of biomimetic puffer skin: Effect of spinal arrangement

In this paper, biomimetic spines on puffer skin were taken as the study object, and numerical simulation was used to study the effect of the spinal arrangement on drag reduction characteristics. The results showed that the drag reduction decreased with the increasing arrangement position (AP) and inflow angle (β), and the drag reduction of the average arrangement was obviously better than that of the staggered arrangement. Moreover, drag reduction increased gradually as the arrangement quantity-R/T (AQR/AQT) increased. The drag reduction increased first and then decreased with the increasing arrangement spacing-R (ASR), and the drag reduction increased as the arrangement spacing-T (AST) increased. In short, the greater the spinal quantity and spacing, the better the drag reduction effect; however, it was affected by the arrangement position, which made the drag reduction effect reduce. More notably, the optimal drag reduction reached 23.1% when the arrangement parameters were the average arrangement, β = 0°, AP = 0 mm, AQR = 11, AQT = 5, ASR = 6.5 mm, and AST = 3.5 mm. Overall, the spinal arrangement parameters can be effectively regulated until the optimal drag reduction was realized, and this work provides a valuable reference for future studies on drag reduction for engineering applications.