Uncovering changes in spider orb-web topology due to aerodynamic effects

An orb-weaving spider's likelihood of survival is influenced by its ability to retain prey with minimum damage to its web and at the lowest manufacturing cost. This set of requirements has forced the spider silk to evolve towards extreme strength and ductility to a degree that is rare among materials. Previous studies reveal that the performance of the web upon impact may not be based on the mechanical properties of silk alone, aerodynamic drag could play a role in the dissipation of the prey's energy. Here, we present a thorough analysis of the effect of the aerodynamic drag on wind load and prey impact. The hypothesis considered by previous authors for the evaluation of the drag force per unit length of thread has been revisited according to well-established principles of fluid mechanics, highlighting the functional dependence on thread diameter that was formerly ignored. Theoretical analysis and finite-element simulations permitted us to identify air drag as a relevant factor in redu...

圆网蛛（orb-weaving spider）的存活概率取决于其以最小蛛网损伤与最低制造成本留存猎物的能力。这一演化需求促使蛛丝朝着极高强度与延展性的方向进化，达到了绝大多数材料都难以企及的水平。既往研究表明，蛛网受冲击时的性能或许并非仅由蛛丝的力学特性决定，空气动力学阻力可能在猎物动能的耗散过程中发挥重要作用。本研究针对空气动力学阻力在风荷载与猎物冲击中的影响开展了全面分析。我们依据成熟的流体力学原理，重新审视了此前研究者用于评估丝线单位长度拖拽力的假设，凸显了此前被忽略的丝线直径对阻力的函数依赖关系。通过理论分析与有限元模拟（finite-element simulations），我们得以确认空气阻力是影响[原文未完整给出]的相关因素。