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Uncertainty Analysis of Neutron Diffusion Eigenvalue Problem Based on Reduced-order Model
Yuanzineng kexue jishu, 2023 In order to improve the efficiency of core physical uncertainty analysis based on sampling statistics, the proper orthogonal decomposition (POD) and Galerkin projection method were combined to study the application feasibility of reduced-order model ...
In order to improve the efficiency of core physical uncertainty analysis based on sampling statistics, the proper orthogonal decomposition (POD) and Galerkin projection method were combined to study the application feasibility of reduced-order model based on POD-Galerkin method in core physical uncertainty analysis. The two-dimensional two group TWIGL benchmark question was taken as the research object, the key variation characteristics of the core flux distribution were extracted under the finite perturbation of the group constants of each material region, and the full-order neutron diffusion problem was projected on the variation characteristics to establish a reduced-order neutron diffusion model. The reduced-order model was used to replace the full-order model to carry out the uncertainty analysis of the group constants of the material region. The results show that the bias of the mathematical expectation of keff calculated by reduced-order and full-order models is close to 1 pcm. In addition, compared with the calculation time required for uncertainty analysis of full-order model, the analysis time of reduced-order model (including the calculation time of the full-order model required for the construction of reduced-order model) is only 11.48%, which greatly improves the efficiency of uncertainty analysis. The biases of mathematical expectation of keff calculated by reduced-order and full-order models based on Latin hypercube sampling and simple random sampling are less than 8 pcm, and under the same sample size, the bias from the Latin hypercube sampling result is smaller. From the TWIGL benchmark test results, under the same sample size, Latin hypercube sampling method is more recommended for POD-Galerkin reduced-order model.
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EXPLORING TRANSIENT, NEUTRONIC, REDUCED-ORDER MODELS USING DMD/POD-GALERKIN AND DATA-DRIVEN DMD [PDF]
EPJ Web of Conferences, 2021 There is growing interest in the development of transient, multiphysics models for nuclear reactors and analysis of uncertainties in those models. Reduced-order models (ROMs) provide a computationally cheaper alternative to compute uncertainties. However,
Elzohery Rabab, Roberts Jeremy
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Buildings, 2023 A common strategy for studying the nonlinear vibrations of beams is to discretize the nonlinear partial differential equation into a nonlinear ordinary differential equation or equations through the Galerkin method.
Yunbo Zhang, Kun Huang, Wei Xu
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On the generalized wavelet-Galerkin method [PDF]
Journal of Computational and Applied Mathematics, 2018 In the frame of the traditional wavelet-Galerkin method based on the compactly supported wavelets, it is important to calculate the so-called connection coefficients that are some integrals whose integrands involve products of wavelets, their derivatives as well as some known coefficients in considered differential equations.
Zhaochen Yang, Shijun Liao
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Advances in Mechanical Engineering, 2019 In this work, we deal with high-order solver for incompressible flow based on velocity correction scheme with discontinuous Galerkin discretized velocity and standard continuous approximated pressure.
Liyang Xu +5 more
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The meshless Galerkin method for pressure distribution simulation of horizontal well reservoir
Petroleum, 2015 This paper provides a novel three-dimensional meshless Galerkin for horizontal well reservoir simulation. The pressure function is approached by moving least-square method which consists of weight function, basic function and coefficient.
Shuyong Hu +3 more
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The simulation of gas-dynamic characteristics of centrifugal compressors in turbo-expander units [PDF]
E3S Web of Conferences, 2019 Prof. Y. Galerkin and his team have developed and completed designs of 19 single-stage centrifugal compressors for turbo-expander packaged units applying Universal Modeling Method for the company “Turbokholod JSC” since 2005. The most powerful compressor
Rekstin A. +4 more
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Journal of Harbin University of Science and Technology, 2022 The equivalence between direct flux reconstruction method and discontinuous Galerkin method for solving parabolic equation and convection-diffusion equation is studied.
BI Hui, LIU Lei
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Discontinuous Galerkin methods for computational aerodynamics - 3D adaptive flow simulation with the DLR PADGE code [PDF]
, 2010 Over the last years, the discontinuous Galerkin method (DGM) has demonstrated its excellence in accurate, high-order numerical simulations for a wide range of applications in computational physics.
Ralf Hartmann +6 more
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Adaptive Fourier-Galerkin methods
Mathematics of Computation, 2013 We study the performance of adaptive Fourier-Galerkin methods in a periodic box in R d
C. Canuto, R. H. Nochetto, VERANI, MARCO
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