Joint Initialization of Flux Networks and Effective Multiplication Factor for Physics-Informed Neural Networks Solving Neutron Diffusion Problems

2026-08-26

AI Summary

为提高有效增殖因子keff的计算效率，提出了一种联合初始化物理信息神经网络(JI-PINN)方法，通过低分辨率近似解来共同优化通量网络参数和keff。

Abstract

Efficient determination of the effective multiplication factor (keff) is an important computational task in reactor core neutronics analysis. Physics-informed neural networks (PINNs) incorporate neutron diffusion equations and boundary conditions into network training to efficiently determine the neutron flux distribution and keff. To further improve the efficiency of keff calculations using PINNs, a Joint Initialization Physics-Informed Neural Network (JI-PINN) is proposed in this work. In this method, a low-resolution approximate solution to the K-eigenvalue problem is used to construct a joint initial state for the flux network parameters and keff, and both are then jointly optimized under physical constraints. The proposed method was validated on a two-dimensional two-group two-material case, the IAEA 2D benchmark, a two-dimensional two-group four-material case, and a three-dimensional single-group case. For these test cases, the total computational time was reduced by 25.4%, 38.2%, 49.4%, and 28.9%, respectively, while comparable solution accuracy was maintained. The occurrence of anomalous results associated with marked deviations of keff from the reference value was also reduced. The proposed method provides a more efficient and robust initialization strategy for solving neutron diffusion K-eigenvalue problem with PINNs.

Problem

• effective multiplication factor
• Physics-informed Neural Networks
• neutron diffusion
• initialization strategy
• K-eigenvalue problem

Innovation

• Joint Initialization
• Physics-Informed Neural Networks
• Neutron Diffusion
• Effective Multiplication Factor
• K-eigenvalue Problem