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DESIGN OF NOVEL HIGH PRESSURE-RESISTANT HYDROTHERMAL fluid SAMPLE VALVE

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Chinese Journal of Mechanical Engineering 2008年第1期21卷 72-76页

作者： LIU Wei YANG Canjun WU Shijun XIE Yingjun CHEN Ying State Key laboratory of fluid power transmission and control Zhejiang University Hangzhou 310027 China

Sampling study is an effective exploration method, but the most extreme environments of hydrothermal vents pose considerable engineering challenges for sampling hydrothermal fluids. Moreover, traditional sampler systems with sample valves have difficulty in maintaining samples in situ pressure. However, decompression changes have effect on microorganisms sensitive to such stresses. To address the technical difficulty of collecting samples from hydrothermal vents, a new bidirectional high pressure-resistant sample valve with balanced poppet was designed. The sample valve utilizes a soft high performance plastic ＂PEEK＂ as poppet. The poppet with inapposite dimension is prone to occur to plastic deformation or rupture for high working pressure in experiments. To address this issue, based on the fmite element model, simulated results on stress distribution of the poppet with different structure parameters and preload spring force were obtained. The static axial deformations on top of the poppet were experimented. The simulated results agree with the experimental results. The new sample valve seals well and it can withstand high working pressure.

关键词： Hydrothermal vents High pressure-resistant Sample valve Finite element analysis Balanced poppet Bidirectional seal

Numerical Simulation of Flow in Centrifugal Pump with Complex Impeller

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Journal of Thermal Science 2011年第1期20卷 47-52页

作者： Bao-ling Cui Yong-gang Lin Ying-zi Jin The laboratory of fluid transmission and Application Zhejiang Sci-Tech University Hangzhou 310018China State Key laboratory of fluid power transmission and control Zhejiang University Hangzhou 310027 China

Based on the Navier-Stokes equations and the Spalart-Allmaras turbulence model,three dimensional turbulent flow fields in centrifugal pump with long-mid-short blade complex impeller are calculated and analyzed *** relative velocity and pressure distributions in the flowpart are *** is found that the flow in the passage of the complex impeller is unsymmetrical due to the joint action between volute and *** back-flow region is at inlet of long-blade suction side,near middle part of long-blade pressure side and outlet of short-blade suction *** flow near volute throat is affected greatly by *** relative velocity is large and it is easy to bring back flow at outlet of the complex impeller near volute *** static and total pressure rise uniformly from inlet to outlet in the *** impeller outlet,the pressure periodically decreases from pressure side to suction side,and then the static pressure sharply rise near the *** experimental results show that the back flow in the impeller has an important influence on the performance of pump.

关键词： Complex impeller Centrifugal pump Numerical simulation Experiment

Enthalpy and Exergy Transfers of High Pressure Switching Expansion Reduction

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Journal of Shanghai Jiaotong university(Science) 2012年第1期17卷 45-52页

作者：罗语溪王宣银雷军波 State Key laboratory of fluid power transmission and control Zhejiang University

The energy balance, air internal energy, enthalpy and exergy transfers of high pressure switching expansion reduction （SER） are comparatively analyzed in this paper to give a better understanding about the exergy analysis and its difference between energy conversion analyses for the pneumatics. In SER, the exergy transfer efficiency is much lower than the enthalpy efficiency. The enthalpy efficiency is primarily related to the initial pressure of supply tanks, and the exergy efficiency is primarily related to the pressure reduction ratios. Heat transfers increase the internal energy, enthalpy and exergy of air; the influence on exergy is relatively small. The total enthalpy in SER decreases as the air temperature decreases in the expansion process of the air. And exergy loss is primarily related to the irreversible process of isenthalpic throttling but not energy conversion. Based on the analyses, to improve the exergy efficiency of the pneumatics, the pressure reduction without power output should be avoided.

关键词： enthalpy exergy energy balance effciency pressure reduction

Reconfigurable Modeling Technology of Similar-structure Products Configuration Design

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Chinese Journal of Mechanical Engineering 2013年第1期26卷 189-196页

作者： QIU Lemiao REN Bin ZHANG Shuyou XU Jian The State Key Lab of fluid power transmission and control Zhejiang University

The product configuration modeling is a key technology to realize configuration design. Most of the researches were mainly conducted focusing on how to establish a product configuration model, but were short of the consideration about the application scope and dynamic change features. In this paper, the reconfigurable modeling technology of similar-structure products configuration design is studied to enhance the generality and diversity of product configuration models, and to facilitate the dynamic upgrade of configuration models. The configuration components of products with similar structures are divided into sharable configuration components, essential configuration components and optional configuration components, so the construction of reconfigurable model of configuration design can be converted into the set operation of configuration components. The horizontal adjusting reconstruction of configuration model is carried out through the adding, replacing and deleting of configuration components, the vertical adjusting reconstruction of configuration model is carried out through the parametric deformation of configuration components, and the variable topological configuration model reconstruction can be realized through the transformation of partial structure of configuration components. Finally, NC machine products are used as an example to analyze and verify the reconfigurable modeling technology of products with similar structures. The speed of NC machine configuration design is found to be improved, and the number of NC machine configuration design models is decreased. And the reconfigurable design system of NC machine products is developed. The proposed modeling technology provides references for the processes, methods and steps of model reconstruction.

关键词： similar-structure products configuration component product configuration model reconstruction

Synchronous tracking control of 6-DOF hydraulic parallel manipulator using cascade control method

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Journal of Central South University 2011年第5期18卷 1554-1562页

作者：皮阳军王宣银顾曦 State Key laboratory of fluid power transmission and control Zhejiang University State Key laboratory of Mechanical transmission Chongqing University

The synchronous tracking control problem of a hydraulic parallel manipulator with six degrees of freedom (DOF) is complicated since the inclusion of hydraulic elements increases the order of the *** solve this problem,cascade control method with an inner/outer-loop control structure is used,which masks the hydraulic dynamics with the inner-loop so that the designed controller takes into account of both the mechanical dynamics and the hydraulic dynamics of the ***,a cross-coupling control approach is introduced to the synchronous tracking control of the *** position synchronization error is developed by considering motion synchronization between each actuator joint and its adjacent ones based on the synchronous ***,with the feedback of both position error and synchronization error,the tracking is proven to guarantee that both the position errors and synchronization errors asymptotically converge to ***,the effectiveness of the proposed approach is verified by the experimental results performed with a 6-DOF hydraulic parallel manipulator.

关键词： synchronization error cross-coupling cascade control hydraulic dynamics parallel manipulator degree of freedom

Nanoparticle coagulation in a planar jet via moment method

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Applied Mathematics and Mechanics(English Edition) 2007年第11期28卷 1445-1453页

作者：于明州林建忠陈丽华 Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang University

Large eddy simulations of nanoparticle coagulation in an incompressible planar jet were performed. The particle is described using a moment method to approximate the particle general dynarnics equations. The time-averaged results based on 3000 time steps for every case were obtained to explore the influence of the Schmidt number and the Damkohler number on the nanoparticle dynamics. The results show that the changes of Schmidt number have the influence on the number concentration of nanoparticles only when the particle diameter is less than 1 nm for the fixed gas parameters. The number concentration of particles for small particles decreases more rapidly along the flow direction, and the nanoparticles with larger Schmidt number have a narrower distribution along the transverse direction. The smaller nanoparticles Coagulate and disperse easily, grow rapidly hence show a stronger polydispersity. The smaller coagulation time scale can enhance the particle collision and coagulation. Frequented collision and coagulation bring a great increase in particle size. The larger the Damkohler number is, the higher the particle polydispersity is.

关键词： nanoparticles coagulation planar jet moment method large eddy simulation

Disassemblability Modeling Technology of Configurable Product Based on Disassembly Constraint Relation Weighted Design Structure Matrix(DSM)

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 511-519页

作者： QIU Lemiao LIU Xiaojian ZHANG Shuyou SUN Liangfeng The State Key Lab of fluid power transmission and control Zhejiang University

The current research of configurable product disassemblability focuses on disassemblability evaluation and disassembly sequence planning. Little work has been done on quantitative analysis of configurable product disassemblability. The disassemblability modeling technology for configurable product based on disassembly constraint relation weighted design structure matrix （DSM） is proposed. Major factors affecting the disassemblability of configurable product are analyzed, and the disassembling degrees between components in configurable product are obtained by calculating disassembly entropies such as joint type, joint quantity, disassembly path, disassembly accessibility and material compatibility. The disassembly constraint relation weighted DSM of configurable product is constructed and configuration modules are formed by matrix decomposition and tearing operations. The disassembly constraint relation in configuration modules is strong coupling, and the disassembly constraint relation between modules is weak coupling, and the disassemblability configuration model is constructed based on configuration module. Finally, taking a hydraulic forging press as an example, the decomposed weak coupling components are used as configuration modules alone, components with a strong coupling are aggregated into configuration modules, and the disassembly sequence of components inside configuration modules is optimized by tearing operation. A disassemblability configuration model of the hydraulic forging press is constructed. By researching the disassemblability modeling technology of product configuration design based on disassembly constraint relation weighted DSM, the disassembly property in maintenance, recycling and reuse of configurable product are optimized.

关键词： disassemblability modeling disassembly entropy disassembling degree weighted DSM product configuration model

Method for Workspace Calculation of 6R Serial Manipulator Based on Surface Enveloping and Overlaying

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Journal of Shanghai Jiaotong university(Science) 2010年第5期15卷 556-562页

作者：王宣银丁渊明 State Key laboratory of fluid power transmission and control Zhejiang University

Aiming at the workspace calculation problem of multi-joint serial manipulators,a surface enveloping and overlaying (SEO) method is presented to identify and visualize the manipulator *** SEO method is composed of two stages:the first stage is to choose reference points of the manipulator and calculate their boundary surfaces using the nth enveloping method;the second stage is to overlay these boundary surfaces to identify the final *** SEO method is basically a combination of the analytic method and the numerical *** delineating the graphic representation of the workspace step by step,the SEO method is easy to analyze the existence and the shape of voids and *** basic theory of the SEO method and formulas for workspace calculation are presented based on a 6R serial *** showing the workspace calculation results,the SEO method is proved working correctly.

关键词： manipulator workspace homogeneous transformation matrix (HTM) rotation transformation matrix (RTM)

Dynamic Performance of High Speed Solenoid Valve with Parallel Coils

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Chinese Journal of Mechanical Engineering 2014年第4期27卷 816-821页

作者： KONG Xiaowu LI Shizhen The State Key Lab of fluid power transmission and control Zhejiang University

The methods of improving the dynamic performance of high speed on/off solenoid valve include increasing the magnetic force of armature and the slew rate of coil current, decreasing the mass and stroke of moving parts. The increase of magnetic force usually leads to the decrease of current slew rate, which could increase the delay time of the dynamic response of solenoid valve. Using a high voltage to drive coil can solve this contradiction, but a high driving voltage can also lead to more cost and a decrease of safety and reliability. In this paper, a new scheme of parallel coils is investigated, in which the single coil of solenoid is replaced by parallel coils with same ampere turns. Based on the mathematic model of high speed solenoid valve, the theoretical formula for the delay time of solenoid valve is deduced. Both the theoretical analysis and the dynamic simulation show that the effect of dividing a single coil into N parallel sub-coils is close to that of driving the single coil with N times of the original driving voltage as far as the delay time of solenoid valve is concerned. A specific test bench is designed to measure the dynamic performance of high speed on/off solenoid valve. The experimental results also prove that both the delay time and switching time of the solenoid valves can be decreased greatly by adopting the parallel coil scheme. This research presents a simple and practical method to improve the dynamic performance of high speed on/off solenoid valve.

关键词： high speed solenoid valve parallel coils dynamic performance delay time