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Theory and Experimental Verification on Valveless Piezoelectric Pump with Multistage Y-shape Treelike Bifurcate Tubes

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Chinese Journal of Mechanical Engineering 2013年第3期26卷 462-468页

作者： HUANG Jun ZHANG Jianhui XUN Xianchao wang shouyin State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics Precision Driving Laboratory Nanjing University of Aeronautics and Astronautics State Key Lab of Digital Manufacturing Equipment & Technology Huazhong University of Science and Technology Foundation Department Aviation University of Air Force Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences

Among most traditional piezo water cooling systems, piezoelectric valve pumps are adopted as their driving sources. The valves in these pumps induce problems of shock and vibration and also make their structure complicated, which is uneasy to minimize and reduce their reliability and applicability of the whole system. In order to avoid these problems caused by valve structure, a novel valveless piezoelectric pump is developed, which integrates both functions of transforming and cooling. The pump’s Y-shape tree-like construction not only increases the efficiency of cooling but also the system reliability and applicability. Firstly, a multistage Y-shape treelike bifurcate tube is proposed, then a valveless piezoelectric pump with multistage Y-shape treelike bifurcate tubes is designed and its working principle is analyzed. Then, the theoretical analysis of flow resistance characteristics and the flow rate of the valveless piezoelectric pump are performed. Meanwhile, commercial software CFX is employed to perform the numerical simulation for the pump. Finally, this valveless piezoelectric pump is fabricated, the relationship between the flow rates and driving frequency, as well as the relationship between the back pressure and the driving frequency are experimentally investigated. The experimental results show that the maximum flow rate is 35.6 mL/min under 100 V peak-to-peak voltage (10.3 Hz) power supply, and the maximum back pressure is 55 mm H2O under 100 V (9 Hz) power supply, which validates the feasibility of the valveless piezoelectric pump with multistage Y-shape treelike bifurcate tubes. The proposed research provides certain references for the design of valveless piezoelectric pump and improves the reliability of piezo water cooling systems.

关键词： piezoelectric pump valveless Y-shape tube treelike bifurcate

Analysis of the Flow Rate Characteristics of Valveless Piezoelectric Pump with Fractal-like Y-shape Branching Tubes

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 628-634页

作者： HUANG Jun ZHANG Jianhui wang shouyin LIU Weidong State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences

Microchannel heat sink with high heat transfer coefficients has been extensively investigated due to its wide application prospective in electronic cooling. However, this cooling system requires a separate pump to drive the fluid transfer, which is uneasy to minimize and reduces their reliability and applicability of the whole system. In order to avoid these problems, valveless piezoelectric pump with fractal-like Y-shape branching tubes is proposed. Fractal-like Y-shape branching tube used in microchannel heat sinks is exploited as no-moving-part valve of the valveless piezoelectric pump. In order to obtain flow characteristics of the pump, the relationship between tube structure and flow rate of the pump is studied. Specifically, the flow resistances of fractal-like Y-shape branching tubes and flow rate of the pump are analyzed by using fractal theory. Then, finite element software is employed to simulate the flow field of the tube, and the relationships between pressure drop and flow rate along merging and dividing flows are obtained. Finally, valveless piezoelectric pumps with fractal-like Y-shape branching tubes with different fractal dimensions of diameter distribution are fabricated, and flow rate experiment is conducted. The experimental results show that the flow rate of the pump increases with the rise of fractal dimension of the tube diameter. When fractal dimension is 3, the maximum flow rate of the valveless pump is 29.16 mL/min under 100 V peak to peak （13 Hz） power supply, which reveals the relationship between flow rate and fractal dimensions of tube diameter distribution. This paper investigates the flow characteristics of valveless piezoelectric pump with fractal-like Y-shape branching tubes, which provides certain references for valveless piezoelectric pump with fractal-like Y-shape branching tubes in application on electronic chip cooling.

关键词： piezoelectric pump valveless fractal-like Y-shape branching tube

Simulation Analysis and Experimental Verification of Spiral-tube-type Valveless Piezoelectric Pump with Gyroscopic Effect

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Chinese Journal of Mechanical Engineering 2014年第4期27卷 822-829页

作者： LENG Xuefei ZHANG Jianhui JIANG Yan wang shouyin ZHAO Chunsheng College of Astronautics Nanjing University of Aeronautics and Astronautics State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences

The current research of the valveless piezoelectric pump focuses on increasing the flow rate and pressure differential. Compared with the valve piezoelectric pump, the valveless one has excellent performances in simple structure, low cost, and easy miniaturization. So, their important development trend is the mitigation of their weakness, and the multi-function integration. The flow in a spiral tube element is sensitive to the element attitude caused by the Coriolis force, and that a valveless piezoelectric pump is designed by applying this phenomenon. The pump has gyroscopic effect, and has both the actuator function of fluid transfer and the sensor function, which can obtain the angular velocity when its attitude changes. First, the present paper analyzes the flow characteristics in the tube, obtains the calculation formula for the pump flow, and identifies the relationship between pump attitude and flow, which clarifies the impact of flow and driving voltage, frequency, spiral line type and element attitude, and verifies the gyroscopic effect of the pump. Then, the finite element simulation is used to verify the theory. Finally, a pump is fabricated for experimental testing of the relationship between pump attitude and pressure differential. Experimental results show that when Archimedes spiral θ=4π is selected for the tube design, and the rotation speed of the plate is 70 r/min, the pressure differential is 88.2 Pa, which is 1.5 times that of 0 r/min rotation speed. The spiral-tube-type valveless piezoelectric pump proposed can turn the element attitude into a form of pressure output, which is important for the multi-function integration of the valveless piezoelectric pump and for the development of civil gyroscope in the future.

关键词： gyroscope valveless piezoelectric pump spiral tube

Theoretical Analysis and Experimental Verification on Valve-less Piezoelectric Pump with Hemisphere-segment Bluff-body

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 595-605页

作者： JI Jing ZHANG Jianhui XIA Qixiao wang shouyin HUANG Jun ZHAO Chunsheng State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics College of Mechanical and Electrical Engineering Qingdao Agricultural University College of Mechanical and Electronic Engineer Beijing Union University Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences

Existing researches on no-moving part valves in valve-less piezoelectric pumps mainly concentrate on pipeline valves and chamber bottom valves, which leads to the complex structure and manufacturing process of pump channel and chamber bottom. Furthermore, position fixed valves with respect to the inlet and outlet also makes the adjustability and controllability of flow rate worse. In order to overcome these shortcomings, this paper puts forward a novel implantable structure of valve-less piezoelectric pump with hemisphere-segments in the pump chamber. Based on the theory of flow around bluff-body, the flow resistance on the spherical and round surface of hemisphere-segment is different when fluid flows through, and the macroscopic flow resistance differences thus formed are also different. A novel valve-less piezoelectric pump with hemisphere-segment bluff-body （HSBB） is presented and designed. HSBB is the no-moving part valve. By the method of volume and momentum comparison, the stress on the bluff-body in the pump chamber is analyzed. The essential reason of unidirectional fluid pumping is expounded, and the flow rate formula is obtained. To verify the theory, a prototype is produced. By using the prototype, experimental research on the relationship between flow rate, pressure difference, voltage, and frequency has been carried out, which proves the correctness of the above theory. This prototype has six hemisphere-segments in the chamber filled with water, and the effective diameter of the piezoelectric bimorph is 30mm. The experiment result shows that the flow rate can reach 0.50 mL/s at the frequency of 6 Hz and the voltage of 110 V. Besides, the pressure difference can reach 26.2 mm H20 at the frequency of 6 Hz and the voltage of 160 V. This research proposes a valve-less piezoelectric pump with hemisphere-segment bluff-body, and its validity and feasibility is verified through theoretical analysis and experiment.

关键词： valve-less piezoelectric pump hemisphere-segment bluff-body flow resistance

Research and test of the measurement sensing device for the downforce of no-till planter row unit gauge wheels

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 250-259页

作者： Jiajie Shang Liyi Liu Ruifeng Zhang Hongcheng Li shouyin Hou Hongxin Liu Haitao Chen College of Engineering Northeast Agricultural UniversityHarbin 150036China College of Mechanical and Electrical Engineering Suqian UniversitySuqian 223800JiangsuChina

To effectively obtain the downforce of the gauge wheels in real time,mechanical models of the interaction among the ground,gauge wheels,gauge wheel arms,and depth adjustment lever were constructed.A measuring method was proposed for monitoring the downforce through a two-dimensional radial sensing device,and a corresponding prototype was *** simulation analysis of the sensing device with ANSYS,a 45°angle was determined to exist between the strain gauge axis and the sensing device axis,and the Wheatstone bridging circuit of R1+R3−R5−R7(R stands for resistance strain gauge,different figures represent the strain gauge number)and R2+R4−R6−R8 was *** to performance and calibration tests for the sensing device,the maximum interaction effect between the X and Y axes was 2.52%,and the output signal was stable and *** standard error of the slope of the fitting equation of the downforce calculation model is *** to the field test,the average downforce of the gauge wheels was 1148,1017,843,and 713 N,at different sowing speeds of 6,8,10,and 12 km/h,*** coefficients of variation were 0.40,0.41,0.62,and 0.71,*** results indicate that the downforce fluctuation of the gauge wheels became more severe with increasing planting *** the strain simulation analysis and field test verified that the measurement method is accurate and reliable,the performance of the sensing device is stable,the measurement method and sensing device meet the application requirements and lay a foundation for the research of accurate and stable control of downforce of no-till planter.

关键词： no-till planter gauge wheel downforce two-dimensional radial force sensing device strain analysis measurement mode and method

西部浅埋厚煤层大断面回采巷道高效跨界支护技术应用研究

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煤炭技术 2022年第3期41卷 71-75页

作者：李军魏琦王守印陕煤集团神木张家峁矿业有限公司陕西神木719300

以张家峁煤矿22202工作面主运巷为工程背景,基于跨界厚层锚固原理提出了适合张家峁煤矿厚煤层大断面回采巷道的高效跨界支护方案,通过理论分析和数值模拟验证了该方案在浅埋厚煤层大断面巷道中应用的可行性,并成功开展了现场工业性试验... 详细信息

以张家峁煤矿22202工作面主运巷为工程背景,基于跨界厚层锚固原理提出了适合张家峁煤矿厚煤层大断面回采巷道的高效跨界支护方案,通过理论分析和数值模拟验证了该方案在浅埋厚煤层大断面巷道中应用的可行性,并成功开展了现场工业性试验,实现巷道掘进速度提高约78.6%,同时矿压观测结果表明新方案实施后相比原支护方案顶板下沉量和两帮收敛量分别降低77%和74.4%,顶板裂隙发育显著减少,实现了该类型煤巷围岩安全控制和掘进效率提升,为西部类似条件千万吨级别矿井实现安全高效开采提供了参考。

关键词：浅埋厚煤层大断面巷道采掘失衡跨界支护

浅埋近距离煤层开采顶板活化结构及支架动载研究

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采矿与安全工程学报 2022年第5期39卷 857-866页

作者：黄庆享王小军贺雁鹏李康华李军刘建浩王守印西安科技大学能源学院教育部西部矿井开采及灾害防治重点实验室陕西西安710054 中煤西安设计工程有限责任公司陕西西安710054 陕煤集团神木张家峁矿业有限公司陕西神木719300

为了揭示上煤层垮落顶板“活化”结构对间隔岩层关键层结构的载荷传递和支架动压机理,以陕北某矿北翼东区1-2与2-2煤层开采为背景,采用物理相似模拟、UDEC数值计算、理论分析及工程实例验证相结合的方法,研究了上煤层垮落顶板“活化”... 详细信息

为了揭示上煤层垮落顶板“活化”结构对间隔岩层关键层结构的载荷传递和支架动压机理,以陕北某矿北翼东区1-2与2-2煤层开采为背景,采用物理相似模拟、UDEC数值计算、理论分析及工程实例验证相结合的方法,研究了上煤层垮落顶板“活化”结构及向下煤层工作面的载荷传递特征,建立了“间隔关键层-上覆垮落顶板活化结构层”双结构力学模型,揭示了浅埋近距离煤层采场支架动载主要由上煤层垮落顶板“活化”结构引起。研究表明:下煤层开采后上煤层垮落顶板“活化”结构层呈现“砌体梁”结构,间隔关键层周期破断后形成“台阶岩梁”结构;上煤层垮落顶板“活化砌体梁”结构与间隔岩层“台阶岩梁”结构同步运动呈现大周期来压,非同步运动呈现小周期来压。通过建立顶板双结构力学模型,给出了支架动载计算公式,得出顶板双结构同步来压载荷作为工作面支架选型的依据,并通过实例分析验证了公式的可靠性。

关键词：浅埋近距离煤层活化结构覆岩动态运移载荷传递支架动载

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类分形Y形分叉流管无阀压电泵的流阻分析

机械工程学报 2014年第16期50卷 193-198页

作者：黄俊张建辉王守印南京航空航天大学机械结构力学及控制国家重点试验室南京210016 江苏大学国家水泵及系统工程技术研究中心镇江212013 中国科学院长春光学精密机械与物理研究所长春130033

以有阀压电泵为应用主流的电子芯片水冷散热系统,因存在阀体的结构原因增加了系统的体积,而且也会因阀体疲劳、失效和性能不稳定等因素影响其可靠性和使用寿命;同时,也还会产生噪声。由于类分形Y形分叉流管无阀压电泵具有简单的二维半... 详细信息

以有阀压电泵为应用主流的电子芯片水冷散热系统,因存在阀体的结构原因增加了系统的体积,而且也会因阀体疲劳、失效和性能不稳定等因素影响其可靠性和使用寿命;同时,也还会产生噪声。由于类分形Y形分叉流管无阀压电泵具有简单的二维半的加工特性及逐级分叉流动能够覆盖更广域面积而产生极佳散热效果可以避免传统有阀压电泵的缺点。介绍类分形Y形分叉流管无阀压电泵的结构及工作原理;利用分形原理对类分形Y形分叉流管的流阻特性进行分析;同时,对类分形Y形分叉流管无阀压电泵进行数值计算与分析,得到该泵进出口间压差与流量关系;制作类分形Y形分叉流管无阀压电泵样机,并对该泵进行流阻和压差试验。试验结果表明,相同压差下,沿流管分流方向流动的出口流量大于合流时的出口流量;当进出口间压差为196 Pa时,试验值与模拟值存在最大相对误差,分流时,为90%,合流时,为89%;当驱动电压为100 V,驱动频率为9 Hz时,泵压差达到最大,为637 Pa。所做研究证明了类分形Y形分叉流管无阀压电泵分流和合流流阻不等,同时也验证了该泵的有效性。

关键词：泵压电分形流阻 Y形

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关于二阶代数免疫布尔函数的几个结果

计算机工程与应用 2011年第30期47卷 68-71页

作者：杜蛟王守印王蕊新乡学院数学系河南新乡453003 北京邮电大学网络与交换技术国家重点实验室北京100876 河南工业大学理学院郑州450001

关于布尔函数的代数免疫性与弹性、代数次数、非线性度之间的关系的结果至今仍然很少,饱和最优布尔函数在流密码领域具有较高的理论价值,通过计算证明文献[1]中命题8给出的5元最优布尔函数都是2阶代数免疫函数,并在此基础上对这个结果... 详细信息

关于布尔函数的代数免疫性与弹性、代数次数、非线性度之间的关系的结果至今仍然很少,饱和最优布尔函数在流密码领域具有较高的理论价值,通过计算证明文献[1]中命题8给出的5元最优布尔函数都是2阶代数免疫函数,并在此基础上对这个结果做了进一步推广。

关键词：布尔函数饱和最优函数零化子代数免疫