俯冲动力学数值模拟中的网格选择  

Computational grid selection in numerical modeling of subduction dynamics

作　　者：杨少华[1,2] 潘家伟 李海兵[1,2] YANG Shaohua;PAN Jiawei;LI Haibing(Key Laboratory of Continental Dynamics of Ministry of Natural Resources,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China;Jiangsu Donghai Continental Deep Hole Crustal Activity National Observation and Research Station,Donghai,Jiangsu 222300,China)

机构地区：[1]中国地质科学院地质研究所,自然资源部大陆动力学重点实验室,北京100037 [2]江苏东海大陆深孔地壳活动国家野外科学观测研究站,江苏东海222300

出　　处：《地质学报》2025年第4期1442-1453,共12页Acta Geologica Sinica

基　　金：中国地质调查局地质调查项目(编号DD20221630);中国地质科学院地质研究所基本科研业务费项目(编号J2316);国家自然科学基金项目(编号42374121);科技部项目(编号2019QZKK0901,2021FY100101)联合资助的成果。

摘　　要：包括俯冲动力学数值模型在内的地学中各种基于数学物理方程的数值模型必然涉及由离散节点组成的计算网格,它控制着数值计算精度进而控制着数值模型在解决实际地球科学问题中的可信度。近年来俯冲动力学数值模拟取得了长足进步,然而随意使用计算网格导致的数值计算误差仍然不清楚。本文针对经典科学问题,基于3套分辨率不同的计算网格构建了数值模型,通过比较不同分辨率计算网格导致的数值结果偏差,评估了低分辨率网格在实际研究过程中的可能影响。本文认为近十年来较常用的加密区分辨率为2 km×2 km的计算网格有可能得到包含明显数值误差的计算结果,进而影响数值模型在地学中的应用。因此,可能有必要重新审视近年来低分辨率网格的模型及其相应的地学结论。随着俯冲动力学有限差分数值模型越来越高的非线性特征,选择尽可能高分辨率的计算网格可能是必然选择。对于高非线性问题使用低分辨率网格的情况,需要确切证据证明网格可靠性。本文提出了一套新的适用于俯冲动力学的网格剖分形式:含悬挂点的局部加密结构化四边形网格。该网格可能在网格总数较少的情况下完成高精度数值计算,并且实现过程相对简单。Various numerical models based on mathematical physics equations in geosciences,including numerical modeling of subduction dynamics,necessarily involve computational grids consisting of discrete nodes,which control the accuracy of numerical calculations and thus the credibility of numerical models in solving practical geoscientific problems.The numerical modeling of subduction dynamics has made great progress in recent years,however,the numerical accuracy due to the arbitrary use of computational grids is still unclear.In this paper,we construct numerical models based on three sets of computational grids with different resolutions for a classical scientific problem,and evaluate the possible impact of low-resolution grids in practical research.It is argued that the computational grid with a resolution of 2 km×2 km for the encrypted zone,which has been more commonly used in the last decade,is likely to obtain computational results containing significant numerical errors,which in turn affects the application of numerical modeling in subduction dynamics.Therefore,it may be necessary to revisit models with low resolution grids and their corresponding geologic conclusions in recent years.As numerical models of subduction dynamics become more and more highly nonlinear,the choice of computational grids with the highest possible resolution may be inevitable.For the case of using low-resolution grids for highly nonlinear problems,definitive evidence of grid reliability is needed.We propose a new set of grid pattern suitable for subduction dynamics:locally encrypted structured quadrilateral grids containing hanging nodes.This grid may accomplish high-precision numerical calculations with a small total number of grids and is relatively simple to implement.

关 键 词：计算网格 数值误差 数值模拟 俯冲动力学 

分 类 号：P631[天文地球—地质矿产勘探]