Journal of Zhejiang University-SCIENCE A最新文献_第10页

Dynamic performance and control accuracy of a novel proportional valve with a switching technology-controlled pilot stage 一种新型开关技术比例阀控制先导级的动态性能及控制精度

IF 3.2 3区工程技术

Journal of Zhejiang University-SCIENCE A Pub Date : 2022-04-01 DOI: 10.1631/jzus.A2100463

Qi Zhong, En-guang Xu, Ting Jia, Huan Yang, Bin Zhang, Yan-biao Li

{"title":"Dynamic performance and control accuracy of a novel proportional valve with a switching technology-controlled pilot stage","authors":"Qi Zhong, En-guang Xu, Ting Jia, Huan Yang, Bin Zhang, Yan-biao Li","doi":"10.1631/jzus.A2100463","DOIUrl":"https://doi.org/10.1631/jzus.A2100463","url":null,"abstract":"Two-stage directional valves usually employ proportional pilot control technology, which has the disadvantages of dead zones, leakage, and the large moving mass of the pilot valve. It is difficult, therefore, to achieve fast-response performance of the main valve. In order to overcome this problem, a switching pilot technology that employs two independent high-speed on/off valves (HSVs) is proposed to replace the traditional pilot proportional valve. Due to the rapid switching characteristics of HSVs, the dead zone of the pilot stage is avoided, and the dynamic response performance of the main valve is improved. The experiments indicate that the switching frequency of the pilot HSVs and supply pressure of the pilot stage have a very large effect on the dynamic performance and control accuracy of the main valve. Increasing the switching frequency of the pilot HSVs is helpful for improving main-valve control accuracy. The larger supply pressure of the pilot stage can achieve a faster dynamic performance of the main valve while causing larger static errors. The results show that the switching pilot technology can clearly improve the static and dynamic performances of the main valve. With the increase of pilot supply pressure, the step rise time is reduced from 21.4 ms to 16.8 ms, and the dynamic performance of the main valve is improved by 21.5%. With the increase of pilot switching frequency, the steady-state error decreases from 24 µm to 20 µm, and the control accuracy of the main valve is improved by 16.7%.","PeriodicalId":17508,"journal":{"name":"Journal of Zhejiang University-SCIENCE A","volume":"16 1","pages":"272 - 285"},"PeriodicalIF":3.2,"publicationDate":"2022-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77346648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Hydraulic directional valve fault diagnosis using a weighted adaptive fusion of multi-dimensional features of a multi-sensor 基于多传感器多维特征加权自适应融合的液压换向阀故障诊断

IF 3.2 3区工程技术

Journal of Zhejiang University-SCIENCE A Pub Date : 2022-04-01 DOI: 10.1631/jzus.A2100394

Jinchuan Shi, Yan Ren, Hesheng Tang, J. Xiang

{"title":"Hydraulic directional valve fault diagnosis using a weighted adaptive fusion of multi-dimensional features of a multi-sensor","authors":"Jinchuan Shi, Yan Ren, Hesheng Tang, J. Xiang","doi":"10.1631/jzus.A2100394","DOIUrl":"https://doi.org/10.1631/jzus.A2100394","url":null,"abstract":"Because the hydraulic directional valve usually works in a bad working environment and is disturbed by multi-factor noise, the traditional single sensor monitoring technology is difficult to use for an accurate diagnosis of it. Therefore, a fault diagnosis method based on multi-sensor information fusion is proposed in this paper to reduce the inaccuracy and uncertainty of traditional single sensor information diagnosis technology and to realize accurate monitoring for the location or diagnosis of early faults in such valves in noisy environments. Firstly, the statistical features of signals collected by the multi-sensor are extracted and the depth features are obtained by a convolutional neural network (CNN) to form a complete and stable multi-dimensional feature set. Secondly, to obtain a weighted multi-dimensional feature set, the multi-dimensional feature sets of similar sensors are combined, and the entropy weight method is used to weight these features to reduce the interference of insensitive features. Finally, the attention mechanism is introduced to improve the dual-channel CNN, which is used to adaptively fuse the weighted multi-dimensional feature sets of heterogeneous sensors, to flexibly select heterogeneous sensor information so as to achieve an accurate diagnosis. Experimental results show that the weighted multi-dimensional feature set obtained by the proposed method has a high fault-representation ability and low information redundancy. It can diagnose simultaneously internal wear faults of the hydraulic directional valve and electromagnetic faults of actuators that are difficult to diagnose by traditional methods. This proposed method can achieve high fault-diagnosis accuracy under severe working conditions.","PeriodicalId":17508,"journal":{"name":"Journal of Zhejiang University-SCIENCE A","volume":"1 1","pages":"257 - 271"},"PeriodicalIF":3.2,"publicationDate":"2022-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82084619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

Mechanism analysis and evaluation of thermal effects on the operating point drift of servo valves 热效应对伺服阀工作点漂移的机理分析与评价

IF 3.2 3区工程技术

Journal of Zhejiang University-SCIENCE A Pub Date : 2022-04-01 DOI: 10.1631/jzus.A2100464

Jian Kang, Zhao Yuan, Jingchao Li

{"title":"Mechanism analysis and evaluation of thermal effects on the operating point drift of servo valves","authors":"Jian Kang, Zhao Yuan, Jingchao Li","doi":"10.1631/jzus.A2100464","DOIUrl":"https://doi.org/10.1631/jzus.A2100464","url":null,"abstract":"Operating point drift over large temperature spans can significantly degrade the performance of servo valves. The direction and magnitude of the deviation of the operating point are uncertain. To analyze and evaluate the mechanism of this complex system with a multi-level structure and multi-variables, it is necessary to construct a theoretical model with a clear physical concept to describe it. However, since the physical processes contain complex variations of structural parameters and flow properties, there is a problem of simplifying approximations in deriving analytical mathematical relations. The advantages of multi-physics field numerical analysis can compensate for this shortcoming of analytical formulations. Based on this, we constructed a whole-valve transfer function model to realize the mechanism analysis and evaluate the operating point drift when a thermal effect acts on a servo valve. The results show that the asymmetric fit relationship between the armature-nozzle assemblies is an important reason for the drift of the operating point caused by the thermal effect. Differences in structural parameters and fluid medium characteristics at different temperatures lead to nonlinear changes in the operating point. When the deviation angle reaches ±1°, an increase in temperature will cause the absolute value of the tangent slope of the displacement deviation of the spool to decrease from 1.44×10−5 m/°C to 1.25×10−6 m/°C. The influence of the deviation angle is reflected in the change in the absolute value of the tangent slope of the pressure deviation from 1. 14×103 Pa/°C to 110 Pa/°C.","PeriodicalId":17508,"journal":{"name":"Journal of Zhejiang University-SCIENCE A","volume":"71 1","pages":"286 - 302"},"PeriodicalIF":3.2,"publicationDate":"2022-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82211428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Data-driven fault diagnosis of control valve with missing data based on modeling and deep residual shrinkage network 基于建模和深度残余收缩网络的缺失数据控制阀故障诊断

IF 3.2 3区工程技术

Journal of Zhejiang University-SCIENCE A Pub Date : 2022-04-01 DOI: 10.1631/jzus.A2100598

Feng Sun, He Xu, Yuhan Zhao, Yudong Zhang

{"title":"Data-driven fault diagnosis of control valve with missing data based on modeling and deep residual shrinkage network","authors":"Feng Sun, He Xu, Yuhan Zhao, Yudong Zhang","doi":"10.1631/jzus.A2100598","DOIUrl":"https://doi.org/10.1631/jzus.A2100598","url":null,"abstract":"A control valve is one of the most widely used machines in hydraulic systems. However, it often works in harsh environments and failure occurs from time to time. An intelligent and robust control valve fault diagnosis is therefore important for operation of the system. In this study, a fault diagnosis based on the mathematical model (MM) imputation and the modified deep residual shrinkage network (MDRSN) is proposed to solve the problem that data-driven models for control valves are susceptible to changing operating conditions and missing data. The multiple fault time-series samples of the control valve at different openings are collected for fault diagnosis to verify the effectiveness of the proposed method. The effects of the proposed method in missing data imputation and fault diagnosis are analyzed. Compared with random and k-nearest neighbor (KNN) imputation, the accuracies of MM-based imputation are improved by 17.87% and 21.18%, in the circumstances of a 20.00% data missing rate at valve opening from 10% to 28%. Furthermore, the results show that the proposed MDRSN can maintain high fault diagnosis accuracy with missing data.","PeriodicalId":17508,"journal":{"name":"Journal of Zhejiang University-SCIENCE A","volume":"120 1","pages":"303 - 313"},"PeriodicalIF":3.2,"publicationDate":"2022-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75027424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Practice of flow control and smart valves 流量控制和智能阀门的实践

IF 3.2 3区工程技术

Journal of Zhejiang University-SCIENCE A Pub Date : 2022-04-01 DOI: 10.1631/jzus.A22FCSV1

J. Qian, Wei Wu, M. Cheng, Jun-hui Zhang

引用次数: 0

Development of amphibious biomimetic robots 两栖仿生机器人的发展

IF 3.2 3区工程技术

Journal of Zhejiang University-SCIENCE A Pub Date : 2022-03-01 DOI: 10.1631/jzus.A2100137

Xiangjuan Bai, Jian Shang, Zirong Luo, Tao Jiang, Qian Yin

{"title":"Development of amphibious biomimetic robots","authors":"Xiangjuan Bai, Jian Shang, Zirong Luo, Tao Jiang, Qian Yin","doi":"10.1631/jzus.A2100137","DOIUrl":"https://doi.org/10.1631/jzus.A2100137","url":null,"abstract":"Amphibious robots are becoming increasingly important for civilian, scientific, and environmental missions. They are widely used in disaster rescue, ecosystem monitoring, and entertainment. However, some have two different locomotion systems that need to be changed manually to fulfill both swimming in the water and moving on land, which may reduce their efficiency and reliability. Applying bioinspiration and biomimetics, many recently developed amphibious robots can undertake various tasks in complex amphibious environments with high mobility, flexibility, and energy efficiency. This review overviews the latest developments in amphibious robots, emphasizing biomimetic design concepts, backbone driving mechanisms, and typical applications. The performance indices of amphibious robots mimicking 13 different natural sources are compared, based on 10 different propulsion principles/modes, travel speed, working efficiency, maneuverability, and stability. Finally, the current challenges and perspectives of amphibious bio-inspired robots are discussed. This article summarizes the current types of amphibious robots and their movement and behavior solutions. The design concepts and operating mechanisms of amphibious robots reviewed here can be readily applied to other robotic studies.","PeriodicalId":17508,"journal":{"name":"Journal of Zhejiang University-SCIENCE A","volume":"11 1","pages":"157 - 187"},"PeriodicalIF":3.2,"publicationDate":"2022-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74473066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

A comparison study between 2D and 3D slope stability analyses considering spatial soil variability 考虑空间土壤变异性的二维与三维边坡稳定性分析对比研究

IF 3.2 3区工程技术

Journal of Zhejiang University-SCIENCE A Pub Date : 2022-03-01 DOI: 10.1631/jzus.A2100139

Liang Zhang, W. Gong, Xinxin Li, Xiao Tan, Chao Zhao, Lei Wang

{"title":"A comparison study between 2D and 3D slope stability analyses considering spatial soil variability","authors":"Liang Zhang, W. Gong, Xinxin Li, Xiao Tan, Chao Zhao, Lei Wang","doi":"10.1631/jzus.A2100139","DOIUrl":"https://doi.org/10.1631/jzus.A2100139","url":null,"abstract":"In engineering practice, the stability of a slope is often analyzed as a 2D problem assuming a plane-strain condition, which may lead to significant errors. In this paper, a comprehensive study is carried out to compare the results of 2D and 3D slope stability analyses, using the strength reduction method for deterministic analysis and the random field approach for probabilistic analysis, respectively. The results of this comparison study confirm that in the deterministic stability evaluation, the 2D analysis tends to obtain a smaller factor of safety than does its 3D counterpart. In the probabilistic evaluation that considers the spatial variability of soil properties, the 2D analysis tends to yield a larger probability of failure than its 3D counterpart. A significant feature of the 3D probabilistic slope stability analysis is the presence of multiple local failures distributed along the slope longitudinal direction. This paper provides insights regarding the degree of errors in modeling a 3D slope as a 2D problem, which can be regarded as a complement to the previous 3D slope stability analyses.","PeriodicalId":17508,"journal":{"name":"Journal of Zhejiang University-SCIENCE A","volume":"19 1","pages":"208 - 224"},"PeriodicalIF":3.2,"publicationDate":"2022-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78571733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Computational fluid dynamics analysis on flow-induced vibration of a cryogenic poppet valve in consideration of cavitation effect 考虑空化效应的低温锥阀流激振动计算流体动力学分析

IF 3.2 3区工程技术

Journal of Zhejiang University-SCIENCE A Pub Date : 2022-02-01 DOI: 10.1631/jzus.A2100118

Aibo Wei, Ronggang Gao, Wei Zhang, Shunyan Wang, Ruijia Zhou, Xiao-bin Zhang

{"title":"Computational fluid dynamics analysis on flow-induced vibration of a cryogenic poppet valve in consideration of cavitation effect","authors":"Aibo Wei, Ronggang Gao, Wei Zhang, Shunyan Wang, Ruijia Zhou, Xiao-bin Zhang","doi":"10.1631/jzus.A2100118","DOIUrl":"https://doi.org/10.1631/jzus.A2100118","url":null,"abstract":"Poppet valves are basic components of many manufacturing operations and industrial processes. The valve plug will withstand unbalanced pressure during the switching process due to the complex fluid-structure interaction (FSI) in the local flow condition, especially with the occurrence of cavitation, which results in a convoluted generation and propagation of mechanical and fluid-dynamic vibrations. In the present work, computational fluid dynamics (CFD) approaches are proposed to model the flow-driven movement of the disc, in consideration of the valve stem rigidity, for a cryogenic poppet valve with liquid nitrogen as the working fluid. Cavitation effects are included in the CFD simulations. The relationship between the displacement of the disc and the resistance of the stem is obtained in advance using the finite element method (FEM), and implemented in CFD calculations based on the user-defined functions (UDFs). The disc vibration is realized using the dynamic mesh technology according to the resultant flow field force and resistance of the stem determined in the UDF. The vibration characteristics of the valve disc, including velocity and vibration frequency, are presented. The temporal evolutions of cavitation behavior due to the vibration are also captured. Comparisons of results between cavitation and non-cavitation conditions are made, and spectral analysis of the transient pressure fluctuations reveals that the presence of cavitation induces transient unbalanced loads on the valve disc and generates instantaneous tremendous pressure fluctuations in the flow field. Various pressure differences between the inlet and outlet as well as valve openings are modeled to probe the influences of FSI on valve disc vibration mechanisms. The consequent analysis gives deeper insights and improves understanding of the mechanism of the complicated interaction between the cavitating flow and the vibration of the valve disc.","PeriodicalId":17508,"journal":{"name":"Journal of Zhejiang University-SCIENCE A","volume":"126 1","pages":"83 - 100"},"PeriodicalIF":3.2,"publicationDate":"2022-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87884470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Erratum to: Effects of the geometrical parameters of the injection nozzle on ethylene-air continuous rotating detonation 喷管几何参数对乙烯-空气连续旋转爆轰的影响

IF 3.2 3区工程技术

Journal of Zhejiang University-SCIENCE A Pub Date : 2022-02-01 DOI: 10.1631/jzus.A20e0314

Wei-jie Fan, Jin Zhou, Shijie Liu, Hao Peng

引用次数: 0

A new technique for high-fidelity cutting technology for hydrate samples 水合物样品高保真切割新技术

IF 3.2 3区工程技术

Journal of Zhejiang University-SCIENCE A Pub Date : 2022-01-01 DOI: 10.1631/jzus.A2100188

Haipei Zhu, Jia-wang Chen, Z. Ren, Peihao Zhang, Qiaoling Gao, Xiaoling Le, C. Xu, K. He, P. Zhou, F. Gao, Yu-ping Fang

{"title":"A new technique for high-fidelity cutting technology for hydrate samples","authors":"Haipei Zhu, Jia-wang Chen, Z. Ren, Peihao Zhang, Qiaoling Gao, Xiaoling Le, C. Xu, K. He, P. Zhou, F. Gao, Yu-ping Fang","doi":"10.1631/jzus.A2100188","DOIUrl":"https://doi.org/10.1631/jzus.A2100188","url":null,"abstract":"Designing a high-fidelity cutting device is one of the difficulties in hydrate samples pressure-holding transfer. Due to the limitations of the existing mechanical system, there is much damage to the cut surface of hydrate samples, with many chips produced, which seriously affects the quality of samples. In this paper, a new cutting device utilizes two servo motors to achieve a high degree of automation. Using the Archimedes spiral, it achieves low disturbance of the cut surface and provides accurate control of the process. In addition, due to the operation of the sample long-stroke push unit, cutting hydrate samples of any length with almost no chips within a short cutting time can be achieved. Laboratory and sea tests have achieved all design requirements of the equipment and strongly demonstrate its benefit and stability. It is concluded that this new high-fidelity cutting technology is practically efficient. The physical state of the hydrate can be maintained to the greatest extent, and thus the new equipment provides significant support for the exploration and development of hydrate resources.","PeriodicalId":17508,"journal":{"name":"Journal of Zhejiang University-SCIENCE A","volume":"20 1","pages":"40 - 54"},"PeriodicalIF":3.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86935265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3