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arXiv · 2502.13190

Application of machine learning algorithm in temperature field reconstruction

Qianyu He·Huaiwei Sun·Yubo Li·Zhiwen You·Qiming Zheng·Yinghan Huang·Sipeng Zhu·Fengyu Wang
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Abstract

This study focuses on the stratification patterns and dynamic evolution of reservoir water temperatures, aiming to estimate and reconstruct the temperature field using limited and noisy local measurement data. Due to complex measurement environments and technical limitations, obtaining complete temperature information for reservoirs is highly challenging. Therefore, accurately reconstructing the temperature field from a small number of local data points has become a critical scientific issue. To address this, the study employs Proper Orthogonal Decomposition (POD) and sparse representation methods to reconstruct the temperature field based on temperature data from a limited number of local measurement points. The results indicate that satisfactory reconstruction can be achieved when the number of POD basis functions is set to 2 and the number of measurement points is 10. Under different water intake depths, the reconstruction errors of both POD and sparse representation methods remain stable at around 0.15, fully validating the effectiveness of these methods in reconstructing the temperature field based on limited local temperature data. Additionally, the study further explores the distribution characteristics of reconstruction errors for POD and sparse representation methods under different water level intervals, analyzing the optimal measurement point layout scheme and potential limitations of the reconstruction methods in this case. This research not only effectively reduces measurement costs and computational resource consumption but also provides a new technical approach for reservoir temperature analysis, holding significant theoretical and practical importance.

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Qianyu He, Huaiwei Sun, Yubo Li, Zhiwen You, Qiming Zheng, Yinghan Huang, Sipeng Zhu, Fengyu Wang. 2025-02-18. Application of machine learning algorithm in temperature field reconstruction. https://arxiv.org/abs/2502.13190

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