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中国丘陵山区农业机械专利技术发展态势

排灌机械工程学报 2024年第9期42卷 965-972页

作者：潘颖孔宝红袁寿其朱兴业江苏大学图书馆江苏镇江212013 江苏大学国家水泵及系统工程技术研究中心江苏镇江212013

基于incoPat专利数据库,从专利视角对中国丘陵山区农业机械技术的成果产出、研发主题、创新主体、成果应用等现状开展分析.结果表明:中国丘陵山区农业机械专利技术在经过近30年的缓慢发展,于2015年进入快速增长期,近5年的年均申请量超70... 详细信息

基于incoPat专利数据库,从专利视角对中国丘陵山区农业机械技术的成果产出、研发主题、创新主体、成果应用等现状开展分析.结果表明:中国丘陵山区农业机械专利技术在经过近30年的缓慢发展,于2015年进入快速增长期,近5年的年均申请量超700件;相比于国外注重农机智能化和精细化研究,中国更侧重山区适用小型机械和园艺机械研究,近年来逐渐重视智能农机和微地形改造探索;高校是该领域的创新主体,其专利申请量占比32.43%;在研发模式方面,合作研发模式占比7.17%,其中企业参与的研发仅占1.10%;科研成果转化应用程度较低,专利转让率为4.78%,许可率为0.58%,质押率为0.54%.针对目前技术发展现状,从深化“政企校”创新模式、聚焦智能农机领域研发、“前+终”两端共同推动专利技术转化等3个方面提出建议.

关键词：农业机械丘陵山区专利分析发展态势技术热点

Dynamic Stress Analysis of Sewage Centrifugal Pump Impeller Based on Two-way Coupling Method

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Chinese Journal of Mechanical Engineering 2014年第2期27卷 369-375页

作者： PEI Ji yuan shouqi yuan Jianping Research Center of Fluid Machinery Engineering and Technology Jiangsu University

Current research on the operational reliability of centrifugal pumps has mainly focused on hydrodynamic instability. However, the interaction between the fluid and structure has not been sufficiently considered; this interaction can cause vibration and dynamic stress, which can affect the reliability. In this study, the dynamic stresses in a single-blade centrifugal pump impeller are analysed under different operating conditions; the two-way coupling method is used to calculate the fluid-structure interaction. Three-dimensional unsteady Reynolds-averaged Navier-Stokes equations are solved with the SST k-o9 turbulence model for the fluid in the whole flow passage, while transient structure dynamic analysis is used with the finite element method for the structure side. The dynamic stresses in the rotor system are computed according to the fourth strength theory. The stress results show that the highest stress is near the loose bearing and that the equivalent stress increases with the flow rate because the dynamic stresses are closely related to the pressure load. The stress distributions on the blade pressure side, suction side, leading edge, and trailing edge are each analysed for different flow rates; the highest stress distribution is found on the pressure side. On the blade pressure side, a relatively large stress is found near the trailing edge and hub side. Based on these results, a stress distribution prediction method is proposed for centrifugal pumps, which considers the interaction between the fluid and structuxe. The method can be used to check the dynamic stress at different flow rates when optimising the pump design to increase the pump reliability.

关键词： numerical analysis fluid-structure interaction single-blade centrifugal pump dynamic stress

Bionics-Inspired Structure Boosts Drag and Noise Reduction of Rotating Machinery

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Journal of Bionic Engineering 2023年第6期20卷 2797-2813页

作者： Shengnan Tang Yong Zhu shouqi yuan Institute of Advanced Manufacturing and Modern Equipment Technology Jiangsu UniversityZhenjiang212013China International Shipping Research Institute GongQing Institute of Science and TechnologyJiujiang332020China National Research Center of Pumps Jiangsu UniversityZhenjiang212013JiangsuChina Saurer(Changzhou)Textile Machinery Co. LtdChangzhou213200China Leo Group Co. LtdWenling317500China Wenling Fluid Machinery Technology Institute of Jiangsu University Wenling317525China

As a global concern,environmental protection and energy conservation have attracted significant *** to the large carbon emission of electricity,promoting green and low-carbon transformation of the power industry via the synergistic development of clean energy sources is *** machinery plays a crucial role in pumped storage,hydropower generation,and nuclear power *** by bionics,non-smooth features of creatures in nature have been introduced into the structure design of efficient rotating ***,the concept and classification of bionics are ***,the representative applications of non-smooth surface bionic structures in rotating machineries are systematically and comprehensively reviewed,such as groove structure,pit structure,and other non-smooth ***,conclusions are drawn and future directions are *** effective design of a bionic structure contributes toward noise reduction,drag reduction and efficiency improvement of rotating *** and ecological rotating machinery will remarkably reduce energy consumption and contribute to the realization of the“double carbon”goal.

关键词： Bionics Rotating machinery Non-smooth surface Pit structure Groove structure

Numerical Investigation on Fluid Structure Interaction Considering Rotor Deformation for a Centrifugal Pump

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Chinese Journal of Mechanical Engineering 2011年第4期24卷 539-545页

作者： yuan shouqi PEI Ji yuan Jianping Research Center of Fluid Machinery Engineering and Technology Jiangsu University Zhenjiang 212013 China

The existing research for unsteady flow field and the corresponding flow induced vibration analysis of centrifugal pump are mainly carried out respectively without considering the interaction between fluid and structure. The ignorance of fluid structure interaction （FSI） means that the energy transfer between fluid and structure is neglected. To some extent, the accuracy and reliability of unsteady flow and rotor deflection analysis should be affected by this interaction mechanism. In this paper, a combined calculation between two executables for turbulent flow and vibrating structure was established using two-way coupling method to study the effect of FSI. Pressure distributions, radial forces, rotor deflection and equivalent stress are analyzed. The results show that the FSI effect to pressure distribution in flow field is complex. The pressure distribution is affected not only around impeller outlet where different variation trends of pressure values with and without FSI appear according to different relative positions between blade and cutwater, but also in the diffusion section of volute. Variation trends of peak values of radial force amplitude calculated with and without FSI are nearly same under high flow rate and designed conditions while the peak value with FSI is slightly smaller, and differently, the peak value with FSI is larger with low flow rate. In addition, the effect of FSI on the angle of radial force is quite complex, especially under 0.5Q condition. Fluctuation of radial deflection of the rotor has obvious four periods, of which the extent is relatively small under design condition and is relatively large under off-design condition. Finally, fluctuations of equivalent stress with time are obvious under different conditions, and stress value is small. The proposed research establishes the FSI calculation method for centrifugal pump analysis, and ensures the existing affect by fluid structure interaction.

关键词： centrifugal pump fluid structure interaction coupled solution unsteady turbulent flow basic theory

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丘陵山区机械化灌溉现状与发展思考

排灌机械工程学报 2024年第3期42卷 294-303页

作者：朱兴业赵莹袁寿其刘俊萍汤玲迪江苏大学国家水泵及系统工程技术研究中心江苏镇江212013

针对目前丘陵山区机械化灌溉装备与技术单一,适应性差,缺少绿色化、智能化的灌溉模式等一系列问题,系统阐述了目前相关研究的现状和未来的发展趋势;全面了解目前丘陵山区机械化灌溉水平是后续开展相关研究的关键.通过分析目前丘陵山区... 详细信息

针对目前丘陵山区机械化灌溉装备与技术单一,适应性差,缺少绿色化、智能化的灌溉模式等一系列问题,系统阐述了目前相关研究的现状和未来的发展趋势;全面了解目前丘陵山区机械化灌溉水平是后续开展相关研究的关键.通过分析目前丘陵山区机械化灌溉的现状,适应丘陵山区机械化发展的要求,在机械化灌溉方面从国家政策入手到丘陵分区,结合丘陵山区的灌溉特点、目前的灌溉现状和相关经济因素进行了系统的总结.根据中国丘陵山区的国情以及相关政策,对丘陵山区机械化灌溉提出了相应的建议.可为未来丘陵山区机械化灌溉改造提供参考,补齐丘陵山区机械化灌溉装备与技术的短板,还可提高对丘陵山区机械化灌溉方面的重视,提升丘陵山区农业的灌溉水平,促进农业跨领域深度联合,推动农业可持续和现代化发展.

关键词：丘陵山区农业机械化灌溉装备机械化灌溉智能化

Numerical analysis of periodic flow unsteadiness in a single-blade centrifugal pump

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Science China(Technological Sciences) 2013年第1期56卷 212-221页

作者： PEI Ji yuan shouqi yuan JianPing Research Center of Fluid Machinery Engineering and Technology Jiangsu University

In this paper,the CFD simulation and new flow unsteadiness analysis for a single-blade centrifugal pump with whole flow passage were carried *** periodic flow unsteadiness has been quantitatively investigated in detail by defining unsteady intensity and turbulence intensity in both rotor and volute domains under design condition Q=33 L s *** results show that the distributions of flow unsteadiness are the functions of impeller rotating angle and have complex unsteady *** obvious T u fluctuations can be also observed for different impeller *** addition,time-averaged unsteady intensity and time-averaged turbulence intensity were calculated by averaging the results of each mesh node for entire impeller revolution period to evaluate the strength distributions of flow unsteadiness directly and *** accumulative results of an impeller revolution can directly show the positions and strength of the flow unsteadiness and turbulence intensity in both rotor and stator domains which can be an important aspect to be considered in the single-blade pump optimum design procedure for obtaining more stable inner flow of the pump and decreasing flow-induced vibration and *** flow unsteadiness in the side chamber cannot be neglected for an accurate prediction of the inner flow of the pump,and the optimizing design procedure for a single-blade pump impeller will not be accurate using CFD tool if the unsteady flow phenomenon in the side chamber is not considered.

关键词： numerical analysis flow unsteadiness turbulence intensity sewage centrifugal pump

Unsteady Turbulent Simulation and Pressure Fluctuation Analysis for Centrifugal Pumps

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Chinese Journal of Mechanical Engineering 2009年第1期22卷 64-69页

作者： yuan shouqi NI Yongyan PAN Zhongyong yuan Jianping Research Center of Fluid Machinery Engineering and Technology Jiangsu University Zhenjiang 212013 China

The pressure fluctuation in the flow passage of both impeller and casing is addressed on design condition. The initial conditions for the unsteady turbulent simulation are resulted from the steady calculations, and the three dimensional unsteady turbulent simulation concerning the rotor-stator interaction is executed by a Navier-Stoke solver embedded with k -ε turbulence model and with appropriate moving interface boundary conditions. Detecting points are distributed in the flow passage in different radial and circumferential positions to capture the static pressure fluctuation character for one cycle of the impeller. The time-domain spectrums show that the static pressure curves are periodic and have five peaks and five valleys. With the radius increasing, the pressure fluctuation peak-to-peak values in the impeller are increasing, and reach the maximum value on the interface. In the casing flow passage, those values are about 7% of local static pressure except some ones near the tongue. The values become decreasingly in the diffuser pipe. The frequency spectrums transformed by fast Fourier transform （FFT） show that the dominant frequency is approximate with the blade passing frequency, and the pressure fluctuations in impeller passage have high frequency content while those in casing ones have no such information.

关键词： centrifugal pump rotor-stator interaction unsteady turbulent flow pressure fluctuation

DETECTION OF CAVITATION IN CENTRIFUGAL PUMP BY VIBRATION METHODS

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Chinese Journal of Mechanical Engineering 2008年第5期21卷 46-49页

作者： NI Yongyan yuan shouqi PAN Zhongyong yuan Jianping Research Center of Fluid Machinery Engineering and Technology Jiangsu University Zhenjiang 212013 China

For the purpose of detecting the cavitation of centrifugal pump onsite and real time, the vibration signals on varied operation conditions of both cavitation and non-cavitation obtained through acceleration sensors were analyzed. When cavitation occurs, the cavities near the leading edge of the blade will appear periodic oscillating, which will induce quasi-synchronous vibration. The frequency of the quasi-synchronous vibration symmetrically appears on the two sides of the blade passing frequency, by which the cavitation incipiency can be detected. During the developing process of the cavitation, as the severe complexity of the unsteady flow, it is very difficult to detect the development of cavitation by classical analysis methods. Fractal method of Higuchi is successfully used for detecting the incipiency, fully development of cavitation and the development between them.

关键词： Centrifugal pump Cavitation Vibration Detection

Numerical and Experimental Study on Flow-induced Noise at Blade-passing Frequency in Centrifugal Pumps

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 606-614页

作者： YANG Jun yuan shouqi yuan Jianping SI Qiaorui PEI Ji Research Center of Fluid Machinery Engineering and Technology Jiangsu University

With the increasing noise pollution, low noise optimization of centrifugal pimps has become a hot topic. However, experimental study on this problem is unacceptable for industrial applications due to unsustainable cost. A hybrid method that couples computational fluid dynamics （CFD） with computational aeroacoustic software is used to predict the flow-induced noise of pumps in order to minimize the noise of centrifugal pumps in actual projects. Under Langthjem＇s assumption that the blade surface pressure is the main flow-induced acoustic source in centrifugal pumps, the blade surface pressure pulsation is considered in terms of the acoustical sources and simulated using CFX software. The pressure pulsation and noise distribution in the near-cutoff region are examined for the blade-passing frequency （BPF） noise, and the sound pressure level （SPL） reached peaks near the cutoff that corresponded with the pressure pulsation in this region. An experiment is performed to validate this prediction. Four hydrophones are fixed to the inlet and outlet ports of the test pump to measure the flow-induced noise from the four-port model. The simulation results for the noise are analyzed and compared with the experimental results. The variation in the calculated noise with changes in the flow agreed well with the experimental results. When the flow rate was increased, the SPL first decreased and reached the minimum near the best efficient point （BEP）; it then increased when the flow rate was further increased. The numerical and experimental results confirmed that the BPF noise generated by a blade-rotating dipole roughly reflects the acoustic features of centrifugal pumps. The noise simulation method in current study has a good feasibility and suitability, which could be adopted in engineering design to predict and optimize the hydroacoustic behavior of centrifugal pumps.

关键词： centrifugal pumps flow-induced noise prediction blade-passing noise blade surface pressure pulsations