5:15 PM - 7:15 PM
[AOS18-P10] Survival Advantage of Claviaster libycus in Mass Extinction and the Impact of Hydraulic Structures on Local Scour Using Discontinuous Bi-viscous Model
Keywords:Splash3D, Discontinuous Bi-Viscous Model, Claviaster libycus, local scour
Previous research suggests that irregular echinoids evolved from early Jurassic regular echinoids, transitioning from living on the seafloor substrate to burrowing into sediment. Unlike the five-fold symmetry of regular echinoids, irregular echinoids exhibit bilateral symmetry. Their survival during mass extinction events is primarily attributed to their burrowing capability, a crucial factor in their success during the Cenozoic era. This raises a fundamental question: What enables the successful survival of irregular echinoids? Is it their burrowing ability or their distinctive morphology? Our hypothesis posits that the unique morphology of irregular echinoids may aid in reducing sediment erosion on the seafloor. If proven, this study could provide insights for mitigating local scour around bridge piers.
This study focuses on Claviaster libycus, a representative of the irregular echinoid subclass, to investigate the survival advantages of irregular echinoids during mass extinction events. We analyze the local scour effects induced by its unique morphology through experimental and numerical modeling approaches. The experimental simulations employ dam-break flows with an impoundment depth of 0.1 meters to replicate extreme flow conditions typical of mass extinction periods. Numerical simulations utilize the Splash3D model, solving the Navier-Stokes equations with the Discontinuous Bi-Viscous Model (DBM) to simulate water flow and sediment transport processes.
Building on the insights into the survival advantages of irregular echinoids, this study explores the potential application of these findings in mitigating local scour around bridge piers. Experimental simulations replicate the scouring effects on irregular echinoids under extreme flow conditions, helping to understand their survival mechanisms while providing an innovative approach for engineering applications. Consequently, both experimental and numerical simulations are conducted on cylindrical and square column piers to assess the factors influencing local scour.
The results indicate that when the gonopore of Claviaster libycus faces downstream, the formation of horseshoe vortices is significantly reduced, thereby decreasing local scour. This supports the study’s hypothesis that the evolution of echinoids from non-burrowing, pentaradial symmetry to burrowing, bilateral symmetry aids in stabilizing bottom sediments and reducing local scour. Both cylindrical and square columns experience considerable local scour, with square columns exhibiting particularly intense scour depths. Further analysis reveals that the larger water-facing area of square columns obstructs flow, leading to stronger downward flows and more pronounced horseshoe vortices. To mitigate local scour around bridge piers, streamlined pier designs are recommended. Additionally, insights from the morphology of Claviaster libycus offer potential applications for developing protective structures to reduce scour around bridge piers.
This study focuses on Claviaster libycus, a representative of the irregular echinoid subclass, to investigate the survival advantages of irregular echinoids during mass extinction events. We analyze the local scour effects induced by its unique morphology through experimental and numerical modeling approaches. The experimental simulations employ dam-break flows with an impoundment depth of 0.1 meters to replicate extreme flow conditions typical of mass extinction periods. Numerical simulations utilize the Splash3D model, solving the Navier-Stokes equations with the Discontinuous Bi-Viscous Model (DBM) to simulate water flow and sediment transport processes.
Building on the insights into the survival advantages of irregular echinoids, this study explores the potential application of these findings in mitigating local scour around bridge piers. Experimental simulations replicate the scouring effects on irregular echinoids under extreme flow conditions, helping to understand their survival mechanisms while providing an innovative approach for engineering applications. Consequently, both experimental and numerical simulations are conducted on cylindrical and square column piers to assess the factors influencing local scour.
The results indicate that when the gonopore of Claviaster libycus faces downstream, the formation of horseshoe vortices is significantly reduced, thereby decreasing local scour. This supports the study’s hypothesis that the evolution of echinoids from non-burrowing, pentaradial symmetry to burrowing, bilateral symmetry aids in stabilizing bottom sediments and reducing local scour. Both cylindrical and square columns experience considerable local scour, with square columns exhibiting particularly intense scour depths. Further analysis reveals that the larger water-facing area of square columns obstructs flow, leading to stronger downward flows and more pronounced horseshoe vortices. To mitigate local scour around bridge piers, streamlined pier designs are recommended. Additionally, insights from the morphology of Claviaster libycus offer potential applications for developing protective structures to reduce scour around bridge piers.