Pufferfish skin is known for its spine-covered surface, which differs significantly from that of common fish species. Recent research has shown that such rough surfaces may have potential applicability in saving energy. In order to verify the drag reduction effects of pufferfish skin, a flat sample and six samples featuring biomimetic spine-covered protrusions (BSCPs) with combinations of three different protrusion heights (0.2, 0.4, and 0.8 mm) and two array patterns (average and staggered) were manufactured. Force measurements and particle image velocimetry (PIV) were introduced with a free-stream velocity of 0.65 ms⁻¹. Drag results suggested that the staggered surface with the shortest BSCPs achieved the best performance, exhibiting the maximum drag reduction of 5.9% compared to the flat sample. Lower Reynolds shear stress and turbulence intensity were achieved over the staggered array according to the PIV results. Less retrograde vortex structures existed inside a viscous buffer sublayer over the BSCPs sample, about 20 ~ 30% in quantity lower than flat one; these prominently influenced the drag reduction effect, as determined by a combination of the \( \upomega \)-criterion and Q-criterion. Furthermore, the coherent structure appeared orderly over the staggered array in the streamwise direction. As a result, the BSCPs height and array pattern are considered influential factors that remain to be optimized in the future for drag reduction.

河豚皮以其脊柱覆盖的表面而闻名，这与常见鱼类的显着不同。最近的研究表明，这样的粗糙表面在节能方面可能具有潜在的适用性。为了验证河豚鱼皮肤的减阻效果，一个平坦的样本和六个具有仿生脊柱覆盖突出物（BSCP）的样本具有三个不同突出高度（0.2、0.4和0.8 mm）和两个阵列模式（平均和交错）被制造。引入力测量和粒子图像测速（PIV），自由流速度为0.65 ms ^-1。阻力结果表明，具有最短BSCP的交错表面获得了最佳性能，与平坦样品相比，最大阻力降低了5.9％。根据PIV结果，在交错阵列上获得了较低的雷诺剪切应力和湍流强度。BSCPs样品上的粘性缓冲液亚层内部不存在逆行涡结构，数量比平面样品低约20〜30％。这些因素明显影响了减阻效果，具体取决于\（\ upomega \）准则和Q准则。此外，相干结构在交错阵列上沿流方向有序出现。结果，BSCP的高度和阵列样式被认为是有影响的因素，这些因素将来有待优化以减少阻力。