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番茄采摘机器人真空吸盘装置设计与试验（Design and Test of the Vacuum Suction Device for Tomato Harvesting Robot）
番茄 采摘机器人 真空吸盘装置 设计
2010/12/29
为实现番茄采摘机器人作业时将目标果实从果束中分离，设计了以微型静音空气压缩机和集成式真空发生器为主体的真空吸盘装置，并依据供气压力-负压关系、吸盘拉脱力和真空吸着响应时间测定结果，确定了其控制策略。试验表明，真空吸盘装置平均单次作业的时间和空气消耗量分别为1.5s和0.6L，拉动果实实现35mm水平位移的成功率达92%，空气压缩机功率可以满足采摘效率360个/h的需要。
气吸滚筒式棉花精量穴播器排种性能试验（Sowing-performance of Air-suction Cylindrical Cotton Precision Dibbler）
棉种 穴播器 气吸滚筒 吸孔线速度
2010/12/28
针对气吸滚筒式精量穴播器作业过程中能耗大、排种性能不稳定等问题，以主要影响因素:取种盘吸孔线速度和充种负压为研究对象进行正交试验、回归分析，确定各因素对排种性能的影响规律及较优工作参数组合。结果表明：充种相对压力-4.5 kPa、取种盘吸孔线速度0.38 m/s时为较优作业参数组合，此条件下穴播器的单粒指数为98.67%、综合评价指数为99.00%、重播指数为0.67%、漏播指数为0.67%，满足...
湍流模型在双吸离心泵数值模拟中的适用性分析（Applicability of Turbulence Models in Numerical Simulation of Double Suction Centrifugal Pump）
离心泵 湍流模型 CFD 数值模拟
2010/12/28
以双吸离心泵为研究对象，在Fluent软件中采用标准k-ε模型、RNG k-ε模型、Realizable k-ε模型和雷诺应力模型4种湍流模型在相同网格条件下进行三维、稳态数值模拟，计算其在不同工况下的扬程及水力效率；然后以RNG k-ε模型计算结果作为初值，用大涡模拟方法进行三维、非稳态数值模拟，计算叶轮旋转一周的平均扬程及平均水力效率，与真机数据进行对比分析。计算结果表明：Fluent软件在...
自吸网式过滤器过滤时间与自清洗时间变化规律分析（Analysis of Filtering Time and Sewage Time for Automatic Suction Screen Filter）
微灌 过滤器 过滤时间
2010/12/28
微灌用过滤器是保证整个微灌系统正常运行的核心过滤设备，开发具有自清洗功能的过滤设备则是研究的重点。在对自吸网式过滤器进行水力性能试验的基础上，分析了自吸网式过滤器过滤时间的变化规律，表明过滤时间的变化并非呈线性规律；分析了自清洗时间的影响因素，指出自清洗时间并不是恒定不变的，而是在其他参数固定时与进水含沙量S0呈反比关系。
Boundary layer flow over a moving surface in a nanofluid with suction or injection
Nanofluid Moving plate Boundary layer Suction/injection Dual solutions
2012/2/24
An analysis is performed to study the heat transfer characteristics of steady two-dimensional boundary layer flow past a moving permeable flat plate in a nanofluid. The effects of uniform suction and ...
Slow Flow of The Reiner-Rivlin Fluid in a Coverging or Diverging Channel with Suction and Injection
Diverging or converging channels porous media viscoelastic fluid intersecting planes
2009/10/14
Two dimensional slow flow of an viscoinelastic fluid in a converging or diverging channel with porous walls has been studied. It is assumed that, the magnitude of the velocity at the center line of th...
Relationship between Methylene Blue Value,Initial Soil Suction and Swell Percent of Expansive Soils
Expansive soil Methylene blue value Psychrometer Swell percent Soil suction
2009/10/12
The purpose of this study was to investigate the relationship between methylene blue value, initial soil suction and the swell percentage of expansive soil samples. In this study, commercially process...
On the Effectiveness of Uniform Suction and Injection on Steady Rotating Disk Flow in Porous Medium with Heat Transfer
Rotating disk flow Heat Transfer Porous medium Suction or Injection
2009/10/10
The steady flow of an incompressible viscous fluid above an in nite rotating porous disk in a porous medium is studied with heat transfer. A uniform injection or suction is applied through the surface...
Time Varying Hydromagnetic Couette Flow with Heat Transfer of a Dusty Fluid in the Presence of Uniform Suction and Injection Considering the Hall Effect
Two phase flow Dusty fluids Heat transfer Hydromagnetic flow
2009/10/9
The time varying Couette flow with heat transfer of a dusty viscous incompressible electrically conducting fluid under the influence of a constant pressure gradient is studied without neglecting the H...
Investigation of Non-Newtonian Micropolar Fluid Flow with Uniform Suction/Blowing and Heat Generation
Stagnation point flow Stretching sheet Heat generation Finite difference method
2009/10/9
The steady laminar flow with heat generation of an incompressible non-Newtonian micropolar fluid impinging on a porous flat plate is investigated. A uniform suction or blowing is applied normal to the...
The Effect of Injection/Suction on Flow past Parallel Plates with Transpiration Cooling
Incompressible Fluid Injection/Suction Skin-Friction Heat Transfer
2009/9/30
This study investigated the effect of injection/suction between 2 horizontal parallel porous flat plates, with transverse sinusoidal injection of fluid at the stationary plate and its corresponding re...
水泵转速变化对进出水流道水力损失的影响（Influence of Rotational Speed of Pumps on Hydraulic Losses in Suction Boxes and Discharge Passages）
水泵 转速 水力损失 进出水流道
2009/8/11
在比较各种进出水流道水力损失研究方法的基础上，运用计算流体动力学方法数值模拟了4种水泵装置内部流动，研究水泵转速变化对进出水流道水力损失的影响。数值计算结果表明，由于水泵装置中进水流道内部流动受水泵叶轮旋转引起的水流预旋的影响，因而小于无泵单独运行时的水力损失。水泵转速变化后，在相同流量下，进水流道的水力损失基本不变。水泵导叶出口水流条件和剩余环量影响出水流道的水力特性，水力损失随流量变化的关系非...
具有诱导轮的高速离心泵汽蚀特性试验（Research on Suction Performance of High-speed Centrifugal Pump with Inducer）
离心泵 高速 诱导轮 汽蚀特性 试验
2010/4/1
采用闭式流体输送试验台，对具有前置诱导轮的高速离心泵进行了汽蚀特性试验研究，比较分析了无诱导轮、单个及串联诱导轮3种工况下诱导轮对离心泵性能及汽蚀性能的影响。发现前置单个或串联诱导轮对离心泵的性能影响并不显著，单个诱导轮的离心泵性能相对于无诱导轮的离心泵性能稍有下降，具有串联诱导轮的离心泵扬程和效率与无诱导轮离心泵相比稍有增加；但采用串联诱导轮可有效提高离心泵的汽蚀性能。 Experimental...
低比转数双吸离心泵回流问题的CFD研究（Simulation of Reverse Flow in Low Specific Speed Double Suction Centrifugal Pump）
双吸离心泵 回流 流场测试
2009/5/22
针对某低比转数双吸离心泵在小流量工况下出现回流的问题，利用CFD技术对双吸泵及吸水室内部流场进行数值模拟研究，并提出定点速度值分析法，模拟流场测试试验中采用的动态探针采样测试系统，对回流问题进行研究。通过对叶轮进口相应测试点在不同流量下的速度变化进行统计分析，发现其变化规律和理论分析结果与以往文献中试验总结的规律变化一致。并根据曲线变化及理论分析结果，提出回流诱发流量点、回流稳定流量点、回流变化区...
Geometry Effect of Air Suction Gun on the Yarn Suction Characteristics
Suction gun Geometry effect Yarn suction force Yarn suction efficiency
2009/4/9
We experimentally discussed the effects of airflow geometries in an air suction gun on the suction characteristics of running yarn. Geometry parameters focused on were 1) compressed-air inflow angle ...