Evidence map›Paper›PMID 33286198›Full record

ArticleEntropy (Basel, Switzerland)2020

Obtaining Information about Operation of Centrifugal Compressor from Pressure by Combining EEMD and IMFE.

Yan Liu, Kai Ma, Hao He, Kuan Gao

Abstract read
In one paragraph

Article in Entropy (Basel, Switzerland), 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

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0 citing papers in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

4 authors.

Yan LiuSchool of Mechanical Engineering, Northwestern Polytechnical University, Xi'an 710072, China.
Kai MaSchool of Mechanical Engineering, Northwestern Polytechnical University, Xi'an 710072, China.
Hao HeSchool of Mechanical Engineering, Northwestern Polytechnical University, Xi'an 710072, China.
Kuan GaoSchool of Mechanical Engineering, Northwestern Polytechnical University, Xi'an 710072, China.

Funding

National Natural Science Foundation of China 51305355National Natural Science Foundation of China 51775437State Key Laboratory of Compressor of China SKL-YSJ201902
6 · The paper itself

Abstract

Based on entropy characteristics, some complex nonlinear dynamics of the dynamic pressure at the outlet of a centrifugal compressor are analyzed, as the centrifugal compressor operates in a stable and unstable state. First, the 800-kW centrifugal compressor is tested to gather the time sequence of dynamic pressure at the outlet by controlling the opening of the anti-surge valve at the outlet, and both the stable and unstable states are tested. Then, multi-scale fuzzy entropy and an improved method are introduced to analyze the gathered time sequence of dynamic pressure. Furthermore, the decomposed signals of dynamic pressure are obtained using ensemble empirical mode decomposition (EEMD), and are decomposed into six intrinsic mode functions and one residual signal, and the intrinsic mode functions with large correlation coefficients in the frequency domain are used to calculate the improved multi-scale fuzzy entropy (IMFE). Finally, the statistical reliability of the method is studied by modifying the original data. After analysis of the relationships between the dynamic pressure and entropy characteristics, some important intrinsic dynamics are captured. The entropy becomes the largest in the stable state, but decreases rapidly with the deepening of the unstable state, and it becomes the smallest in the surge. Compared with multi-scale fuzzy entropy, the curve of the improved method is smoother and could show the change of entropy exactly under different scale factors. For the decomposed signals, the unstable state is captured clearly for higher order intrinsic mode functions and residual signals, while the unstable state is not apparent for lower order intrinsic mode functions. In conclusion, it can be observed that the proposed method can be used to accurately identify the unstable states of a centrifugal compressor in real-time fault diagnosis.

Indexed as

centrifugal compressorensemble empirical mode decompositionmulti-scale fuzzy entropynonlinear dynamicssurge

Identifiers

PMID33286198
PMCPMC7516900

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