Modeling how shark and dolphin skin patterns control transitional wall-turbulence vorticity patterns using spatiotemporal phase reset mechanisms.
Modeling how shark and dolphin skin patterns control transitional wall-turbulence vorticity patterns using spatiotemporal phase reset mechanisms.
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DOI：
10.1038/srep06650
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发表时间：
2014-10-23
影响因子：
4.6
通讯作者：
Hellum AM
中科院分区：
文献类型：
--
作者：
Bandyopadhyay PR;Hellum AM
许多缓慢移动的生物系统，如贝壳和斑马鱼，不与壁湍流相抗衡，具有与其外表面齐平的某种组织化的色素沉着模式，这些模式是由潜在的自主反应扩散（RD）机制形成的。相比之下，鲨鱼和海豚与壁湍流相抗衡，是快速游泳者，并且具有更有组织的皮肤图案，这些图案是自豪的，有时会振动。一个非线性的时空分析模型是不可用的，解释了这种自豪的模式的流动控制的机制，尽管鲨鱼和海豚的皮肤是阻力和噪音减少的逆向工程机制的主要目标。相比RD，一个最小的自我调节模型给出了壁湍流再生的过渡制度横向耦合，扩散，虽然限制到预击穿的持续时间和一个平面接近和平行的墙壁，正确地再现了许多实验观察到的时空组织的涡在两个层流湍流过渡和非常低的雷诺数，但湍流区域。我们进一步表明，如果将皮肤组织作为橄榄-小脑相位重置机制的时空模板，则涡度紊乱的发生会延迟。该模型表明，鲨鱼和海豚对流体环境的适应机制有许多共同之处。
Many slow-moving biological systems like seashells and zebrafish that do not contend with wall turbulence have somewhat organized pigmentation patterns flush with their outer surfaces that are formed by underlying autonomous reaction-diffusion (RD) mechanisms. In contrast, sharks and dolphins contend with wall turbulence, are fast swimmers, and have more organized skin patterns that are proud and sometimes vibrate. A nonlinear spatiotemporal analytical model is not available that explains the mechanism underlying control of flow with such proud patterns, despite the fact that shark and dolphin skins are major targets of reverse engineering mechanisms of drag and noise reduction. Comparable to RD, a minimal self-regulation model is given for wall turbulence regeneration in the transitional regime—laterally coupled, diffusively—which, although restricted to pre-breakdown durations and to a plane close and parallel to the wall, correctly reproduces many experimentally observed spatiotemporal organizations of vorticity in both laminar-to-turbulence transitioning and very low Reynolds number but turbulent regions. We further show that the onset of vorticity disorganization is delayed if the skin organization is treated as a spatiotemporal template of olivo-cerebellar phase reset mechanism. The model shows that the adaptation mechanisms of sharks and dolphins to their fluid environment have much in common.
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影响因子：
4.6
作者：
Bandyopadhyay, Promode R.;Hansen, Joshua C.
通讯作者：
Hansen, Joshua C.
影响因子：
3.7
作者：
CHOI, KS
通讯作者：
CHOI, KS
影响因子：
4.6
作者：
Bandyopadhyay, PR;Henoch, C;Escudier, MP
通讯作者：
Escudier, MP
影响因子：
4.6
作者：
BANDYOPADHYAY, PR;HUSSAIN, AKMF
通讯作者：
HUSSAIN, AKMF
DOI：
10.1063/1.858292
发表时间：
1992-04-01
期刊：
PHYSICS OF FLUIDS A-FLUID DYNAMICS
影响因子：
--
作者：
ALBAREDE, P;MONKEWITZ, PA
通讯作者：
MONKEWITZ, PA