抗磨液压油试验高压泵摩擦副磨损过程分析及其模拟

按高压泵的磨损情况来评定油品质量是抗磨液压油研究的重要内容之一,本文通过建立的试验泵模拟试验方法,对抗磨液夺油试验用高压泵的磨损情况深入研究,此项研究不仅为我国抗磨液压油品质量的评定提供了重要的分析依据,同时也为高压泵摩擦材料的合理选择,磨损机理的分析研究奠定了基础。     

核电站反应堆冷却剂泵的模态分析

以某核电站反应堆冷却剂泵（以下简称核泵）为研究对象,对核泵结构进行适当简化后,建立有限元模型,并在有连杆和无连杆两种工况下,计算核泵的固有频率,得出了其前12阶固有频率和振型,并结合核泵具体结构对其固有频率和振型进行了简要说明,计算了阻尼器、拉杆和立柱刚度对核泵固有频率的影响。分析结果可以为下一步进行核泵的地震响应分析提供理论依据。     

浪店水源泵站工程应用大型潜水轴流泵的可行性

浪店水源工程位于黄河小北干流，该河段河势游荡不定，引水口位置难以确定，为了适应河势变化，提高取水保证率，取得长远较好的社会效益，拟采用可移动的大型潜水轴流泵。本文就该工程应用此泵的可行性作一分析。     

电液比例变量泵控定量马达调速特性研究

以电液比例变量泵-定量马达恒速控制系统为研究对象,详细阐述了变量泵电液比例变量机构的控制原理,分析了变量泵的斜盘机构受力情况,推导了变量机构和泵控马达系统的数学模型.分别在仿真软件MATLAB/Simulink和AMESim上建立变量机构和变量泵控马达系统的仿真模型,对变量机构响应时间和马达输出转速响应进行了仿真研究和试验对比.利用发电机为恒转速负载,进行了实车试验.在突加/突减16 kW负载的试验中,马达转速在3 s内恢复到设定值,稳态的波动率为0.29%,瞬态调整率为6.0%.分析结果表明,电液比例变量泵控马达系统作为柴油机和恒转速负载之间的调速机构和动力传递纽带是可行的.     

A virtual yaw rate sensor for articulated vehicles featuring novel electro-hydraulic steer-by-wire technology

Steer-by-wire technologies remain under rigorous research and development given the advantages that they offer over their traditional counterparts. The spectrum of steering systems encompasses applications in the automotive, construction, agricultural, and aerospace industries, to name a few.An original electro-hydraulic steer-by-wire technology based on pump displacement control actuation, an energy efficient alternative to conventional valve control, has been previously proposed by the authors. The new concept was validated and implemented on an articulated steering prototype test vehicle, and resulted in significant fuel savings and machine efficiency increase. This paper investigates the notion of virtual sensing relative to estimating the vehicle׳s yaw rate by only measuring the articulation angle and vehicle speed. Virtual sensing is a promising concept for yaw stability control and is an attractive option for vehicle manufactures as it reduces sensor cost, maintenance, and machine downtime. The designed yaw rate sensor is validated in simulation as well as on a test vehicle by devising appropriate steering maneuvers.     

上海地区应用燃气热泵的天然气定价探讨

简要介绍了燃气热泵(GHP)和电动多联机(EHP)的性能;对上海的几种典型用户,按照负荷配置目标建筑的室内、室外机,计算其逐时负荷,确定GHP机组的全年天然气耗量、辅助电耗等,并与实际耗气量进行比较;作为对比,同样计算确定EHP的耗电量;结合现行的电价和天然气价格,分析GHP机组的经济性并提出建议的分季节天然气价格。     

Optimal design of gear pumps for exhaust gas aftertreatment applications

In this paper an innovative procedure for determining the optimal design of an external spur gear pump for a particular emission reduction application in automobiles has been proposed. The pump forms the main part of a mechatronic system that controls the flow rate of a mixture of urea in water to catalytically reduce emissions in diesel engines. The proposed research proves to be an advance in gear machine design by using a multi-objective based genetic algorithm, to determine the optimal design of the gears and the casing by maximizing the volumetric efficiency, minimizing pressure overshoots, localized cavitation and noise emissions. The research uses HYGESim (HYdraulic GEar machines Simulator) simulation tool, which is being developed by the authors’ research group, for calculating the important performance features of the machine. The best designs for the machine based on enhancement in performance are presented. Results in terms of simulations and tests which validate the effectiveness of the proposed novel design methodology are also presented.     

Energy efficient control of variable speed pumps in complex building central air-conditioning systems

This paper presents the optimal control strategies for variable speed pumps with different configurations in complex building air-conditioning systems to enhance their energy efficiencies. Through a detailed analysis of the system characteristics, the pressure drop models for different water networks in complex air-conditioning systems are developed and then used to formulate an optimal pump sequence control strategy. This sequence control strategy determines the optimal number of pumps in operation taking into account their power consumptions and maintenance costs. The variable speed pumps in complex air-conditioning systems can be classified into two groups: the pumps distributing water to terminal units and pumps distributing water to heat exchanges. The speeds of pumps distributing water to terminal units are controlled by resetting the pressure differential set-point using the online opening signals of water control valves. The speeds of pumps distributing water to heat exchanges are controlled using a water flow controller. The performances of these strategies are tested and evaluated in a simulated virtual environment representing the complex air-conditioning system in a super high-rise building by comparing with that of other reference strategies. The results showed that about 12-32% of pump energy could be saved by using these optimal control strategies.     

用热力学法对泵效率,流量进行测定及在线监测的应用研究

本文结合我国现行的常规法泵测试标准ＧＢ３２１６－８９．对泵效率、流量的热力学法测定及在线监测的实际应用进行了综合研究。指出：在现阶段，对电厂锅炉给水泵采用热力学法进行效率、流量测定及在线监测是完全对行的，而对一般工业用泵，则需研制更高精度的测温元件；同时，对测温仪表的精度和可靠性给出了简易、可靠的自样验方法。     

大中型泵站现场流量测试技术及应用

大中型泵站机组的现场流量精确测试，长期以来一直被认为是个难题，在国内属于起步阶段。根据美国ACCUSONIC公司的7510P型移动式多声路超声波流量计在低水头泵站的单机流量测量原理，结合在江都二站进行的仪器验收试验，介绍了超声波沆量计在低水头泵站中测试方法，并对流量、效率试验成果作了介绍。多声路超声波流量计的成功应用，增添了国内低水头泵站现场流量精确测试的新方法，为今后类似泵站的流量、效率测量应用积累了经验，同时对泵站的设计、建设和管理将起到积极作用。