基于生死单元动态演化的混凝土坝温度场等几何仿真方法OA
An isogeometric simulation method for the temperature field of concrete dams based on dynamic evolution of birth-death elements
高精度温度场数值仿真对严苛环境下混凝土坝的设计运行至关重要.然而,有限元分析中离散生成的网格模型与真实几何模型之间存在差异,尤其对于包含复杂边界的结构,这种以多边形网格逼近光滑几何的差异更加明显.针对这种模型误差,目前缺乏有效量化手段,导致基于误差模型的数值计算结果难以保证精度.为探究模型误差对温度场计算精度的影响机制,提出离散几何保真度误差(DGFE)新指标,以定量表征几何模型与网格模型的差异,通过对比计算等几何分析与有限元分析的DGFE指标,验证了等几何分析方法具有更高的几何精确性与数值求解精度.为实现混凝土坝温度场的高精度仿真,开发了等几何分析热传导计算方法,并应用于坝后背管及冷却水管等典型结构的温度场模拟,结果表明该方法兼具优良的求解精度与计算效率.针对混凝土坝施工期分层浇筑的特点,将生死单元技术与等几何分析深度融合,模拟了实际混凝土坝施工期温度场的动态演化过程,选取两个典型测点进行温度分析,仿真结果与实测数据高度吻合,相对误差分别为3.8%和2.8%,证实了等几何分析在混凝土坝温度场动态仿真计算中的有效性,为该类复杂结构的温度场分析提供了一种几何精确且高精度的数值仿真手段.
High-precision numerical simulation of temperature fields is crucial for the design and operation of con-crete dams under severe conditions.However,in finite element analysis(FEA),the discretized mesh model often deviates from the true geometric model,especially for structures with complex boundaries,where polygonal meshes approximate smooth geometries imperfectly.Currently,there is a lack of effective methods to quantify such model errors,making it difficult to guarantee the accuracy of numerical results based on error-affected models.To investi-gate how model errors influence the accuracy of temperature field calculations,a new metric—Discrete Geometry Fidelity Error(DGFE)—was proposed to quantitatively characterize the discrepancy between the geometric model and the mesh model.By comparing the DGFE of isogeometric analysis(IGA)and FEA,it was demonstrated that IGA can achieve higher geometric accuracy and numerical precision.For high-fidelity simulation of temperature fields in concrete dams,a heat conduction analysis method based on IGA was developed and applied to typical structures such as penstocks behind dams and cooling water pipes.The results show that this method offers both high solution accu-racy and computational efficiency.Considering the layered construction process of concrete dams,the birth-death element technique was integrated with IGA to simulate the dynamic evolution of the temperature field during actual dam construction.Temperature analysis at two typical monitoring points revealed close agreement between simulation results and field measurements,with relative errors of only 3.8%and 2.8%,respectively.This confirms the effective-ness of IGA for dynamic thermal simulation in concrete dams,providing a geometrically precise and high-accuracy numerical approach for temperature field analysis of such complex structures.
李明超;李昂;张梦溪;王亦欣;何殷鹏
水利工程智能建设与运维全国重点实验室,天津大学,天津 300350||新疆工业学院 水利水电学院,新疆 和田 848000水利工程智能建设与运维全国重点实验室,天津大学,天津 300350水利工程智能建设与运维全国重点实验室,天津大学,天津 300350||新疆工业学院 水利水电学院,新疆 和田 848000水利工程智能建设与运维全国重点实验室,天津大学,天津 300350水利工程智能建设与运维全国重点实验室,天津大学,天津 300350
建筑与水利
混凝土坝温度场离散几何保真度误差等几何分析生死单元
concrete damtemperature fielddiscrete geometric fidelity errorisogeometric analysisbirth-death elements
《水利学报》 2026 (2)
194-206,13
国家自然科学基金项目(52309166,524B2134)天津市青年科技人才项目(QN20230328)
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