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A Novel De-noising Method Based on Discrete Cosine Transform and Its Application in the Fault Feature Extraction of hydraulic pump

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Journal of Shanghai Jiaotong university(Science) 2016年第3期21卷 297-306页

作者：王余奎黄之杰赵徐成朱毅魏东涛 Air Force Logistics College of PLA Xuzhou 221000JiangsuChina Ordnance Engineering College of PLA Shijiazhuang 050003China

Aiming at the existing problems of discrete cosine transform(DCT) de-noising method, we introduce the idea of wavelet neighboring coefficients(WNC) de-noising method, and propose the cosine neighboring coefficients(CNC) de-noising method. Based on DCT, a novel method for the fault feature extraction of hydraulic pump is analyzed. The vibration signal of pump is de-noised with CNC de-noising method, and the fault feature is extracted by performing Hilbert-Huang transform(HHT) to the output signal. The analysis results of the simulation signal and the actual one demonstrate that the proposed CNC de-noising method and the fault feature extraction method have more superior ability than the traditional ones.

关键词： discrete cosine transform(DCT) de-noising method cosine neighboring coefficients(CNC) de-noising method hydraulic pump fault feature extraction

Research Status, Critical Technologies, and Development Trends of hydraulic Pressure Pulsation Attenuator

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Chinese Journal of Mechanical Engineering 2021年第1期34卷 114-130页

作者： Yan Wang Tongsheng Shen Chunsen Tan Jian Fu Shengrong Guo School of Transportation Science and Engineering Beihang UniversityBeijing 100083China School of Mechanical Engineering and Automation Beihang UniversityBeijing 100083China Nanjing Engineer Institute of Air-craft Systerm Jincheng AVICNanjing 211100China

hydraulic pumps are a positive displacement pump whose working principle causes inherent output flow pulsation.Flow pulsation produces pressure pulsation when encountering liquid resistance.Pressure pulsation spreads in the pipeline and causes vibration,noise,damage,and even pipeline rupture and major safety accidents.With the development of airborne hydraulic systems with high pressure,power,and flow rate,the hazards of vibration and noise caused by pressure pulsation are also amplified,severely restricting the application and development of hydraulic systems.In this review paper,the mechanism,harm,and suppression method of pressure pulsation in hydraulic systems are analyzed.Then,the classification and characteristics of pulsation attenuators according to different working principles are described.Furthermore,the critical technology of simulation design,matching method with airborne piston pumps,and preliminary design method of pulsation attenuators are proposed.Finally,the development trend of pulsation attenuators is prospected.This paper provides a reference for the research and application of pressure pulsation attenuators.

关键词： hydraulic pump Pressure pulsation Pulsation attenuator

Performance optimization of grooved slippers for aero hydraulic pumps

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Chinese Journal of Aeronautics 2016年第3期29卷 814-823页

作者： Chen Juan Ma Jiming Li Jia Fu Yongling Department of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Sino-French Engineer School Beihang UniversityBeijing 100191China AVIC Xi'an Flight Automatic Control Research Institute.Xi'an 710065 China

A computational fluid dynamics （CFD） simulation method based on 3-D Navier Stokes equation and Arbitrary Lagrangian Eulerian （ALE） method is presented to analyze the grooved slip- per performance of piston pump. The moving domain of grooved slipper is transformed into a fixed reference domain by the ALE method, which makes it convenient to take the effects of rotate speed, body force, temperature, and oil viscosity into account. A geometric model to express the complex structure, which covers the orifice of piston and slipper, vented groove and the oil film, is constructed. Corresponding to different oil film thicknesses calculated in light of hydrostatic equilibrium theory and boundary conditions, a set of simulations is conducted in COMSOL to analyze the pump characteristics and effects of geometry （groove width and radius, orifice size） on these characteristics. Furthermore, the mechanics and hydraulics analyses are employed to validate the CFD model, and there is an excellent agreement between simulation and analytical results. The simulation results show that the sealing land radius, orifice size and groove width all dramatically affect the slipper behavior, and an optimum tradeoff among these factors is conducive to optimizing the pump design.

关键词： Arbitrary LagrangianEulerian （ALE） Computational fluid dynam-ics （CFD） Grooved slipper hydraulic pump Navier-Stokes equation Performance analysis

Control System Development of the One-axis hydraulic Road Simulator Using QFT

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Control System Development of the One-axis Hydraulic Road Si...