浅析大涡模拟在古生态学中的应用  

LARGE EDDY SIMULATIONS AND ITS APPLICATION IN PALAEOECOLOGY

作　　者：冯文谦 李启剑[1] 那琳[1] 张景新[3,4] 李越[1] FENG Wenqian;LI Qijian;NA Lin;ZHANG Jingxin;LI Yue(Key Laboratory of Palaeobiology and Petroleum Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academyof Sciences,Nanjing210008,China;University of Chinese Academy of Sciences,Beijing 100049,China;School of Naval Architecture,Ocean&Civil Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;MOE Key Laboratory of Hydrodynamics,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]古生物学与油气地层应用重点实验室,中国科学院南京地质古生物研究所,南京210008 [2]中国科学院大学,北京210008 [3]上海交通大学船舶海洋与建筑工程学院,上海200240 [4]上海交通大学水动力学教育部重点实验室,上海200240

出　　处：《微体古生物学报》2024年第1期65-77,共13页Acta Micropalaeontologica Sinica

基　　金：国家自然科学基金(42372039);中国科学院青促会项目(2019310)共同资助。

摘　　要：计算流体力学(CFD)作为一种用计算机来模拟流体实际流动情况的前沿分析方法,是流体力学问题的定量化求解工具。近年来, CFD在古生态学(特别是化石功能学)方面得到了越来越广泛的应用。虽然CFD包含多种湍流计算模型,但早期对古生物化石的仿真模拟实验主要基于雷诺平均数值模拟(RANS)。本文以寒武纪已灭绝的高钙化海绵动物——“规则”古杯动物化石模型为例,应用基于大涡模拟(LES)的湍流数值计算模型进行相关的流体力学模拟与分析。同时,应用RANS模型并以相同的流体动力学参数进行仿真模拟,从而详细比较不同计算模型间的差异。CFD结果重现了古杯动物在海底古水流环境下的流体力学特征, LES和RANS实验共同揭示了“规则”古杯动物独特的骨骼形态在其滤食以及有性繁殖等方面的适应性优势。与RANS模型相比, LES这一计算模型在本案例中呈现出更高精度的模拟结果,值得在相关研究中作进一步的推广。Computational fluid dynamics(CFD) is a simulation method that emulates the real fluid flow in a digital environment, providing quantitative solutions to the fluid mechanics problems. In the past decade, CFD has gained prominence in reconstructing the function and paleoecology of ancient and mysterious fossils through numerical simulations of the fluid flows. While various turbulence models have been developed in CFD, earlier computer experiments on extinct organisms mostly relied on the Reynolds-averaged Navier-Stokes(RANS) equations. In this study, we conducted a biomechanical analysis using ‘regular' archaeocyaths as a case study, employing the large eddy simulations(LES) turbulence model. Additionally, the RANS model was applied for comparative simulations under identical fluid dynamic settings. The CFD analyses accurately replicate the hydrodynamic conditions on the seafloor where archaeocyaths lived. Both RANS and LES experiments unveil the intricate influence of the skeletal motifs of archaeocyaths on the flow physics within and beyond their central cavities. Compared to the RANS model, the LES model exhibits higher precision in the quantitative analysis of paleoecology.

关 键 词：大涡模拟 计算流体力学 古生态 生物力学 古杯动物 

分 类 号：Q915.2[天文地球—古生物学与地层学]