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双语推荐：驼峰特性

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为了研究可逆式水泵水轮机泵工况的驼峰特性,通过非定常分离涡模拟（DES）的方法,计算不同流量工况下机组的内部流场特征.根据机组对应工况下的模型试验,对机组流道中的流态特征进行对比分析,特别对扩散流道损失以及转轮与导叶之间的动/静干涉现象进行研究,探讨驼峰特性产生的具体原因.结果表明：机组在小流量工况下运行时,转轮出口流动呈现明显非对称性;紊乱的流动特征引发转轮内部与扩散段中产生涡结构与二次流结构;由于不良流态的出现,过流部件水力损失显著上升,并引发扬程的下降,导致机组形成扬程-流量曲线的驼峰区域.因此,改善小流量工况下转轮内部流态对于改善水泵水轮机驼峰特性具有重要的作用.该研究内容阐明了驼峰特性对水泵水轮机造成不良影响的机理,对改进机组水泵工况的水力性能提供了参考与帮助,对于水泵水轮机的稳定运行具有重要意义.
To investigate the hump characteristic in discharge-head curve of reversible pump-turbines in pump mode,the internal flow field of a pump-turbine unit is simulated in its pump mode under dif-ferent flow-rate conditions by employing the detached eddy simulation (DES)method.The underlying mechanism for the hump characteristic is exploited by comparing the CFD and experimental character-istics of flow inside each passage of the unit,especially for the hydraulic losses in the diffusing passage and for the rotor-stator interaction.The results show that the flow exhibits an obviously asymmetric pat-tern at the runner outlet as the unit is operated in the low discharge range.The asymmetric flow field is caused from the vortex and secondary flow generated in the diffusing portion of the runner passages.As a result,the hydraulic losses in the unit rise dramatically,causing a reduction in the pump head,e-ventually the hump characteristic occurs.Nevertheless,improving the flow pattern u

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针对水泵水轮机泵工况流量-扬程曲线的驼峰特性,采用SSTk-ω湍流模型对水泵水轮机进行模拟,并研究定常与非定常模拟对流量-扬程特性的预测准确性。建立活动导叶开度为20°的水泵水轮机全流道模型,对于非定常模拟,在尾水管(吸水室)-转轮与转轮-活动导叶两动静交接面处,分别设置考虑瞬态效应的TRS(Transient Rotor Stator)模型,模拟预测机组流量-扬程关系,分析各过流部件扬程损失并研究驼峰区产生机理。模拟结果表明,泵工况下水泵水轮机流量-扬程驼峰特性与固定部件内部涡结构及其所致损失紧密相关。相比定常模拟,瞬态非定常模拟结果与试验值更为吻合,且在交接面前后相邻处速度场变化平缓,符合实际流动规律。考虑交接面瞬态作用的非定常模拟能够更加准确地模拟水泵水轮机等叶轮机械在非设计工况下的流动,为改善水泵水轮机运行稳定性提供有效的参考。
The unstable head-discharge characteristic affects the stability and security of pump-turbine.In pump mode,the unstable phenomenon may occur when the pump-turbine is starting,shutting down or running at the maximum head condition.To investigate this phenomenon,numerical simulation with SST k-ωturbulence model was conducted.Both steady and transient analysis type were used to forecast the head-discharge characteristic.The whole flow passage was modeled with the adj ustable vane opening an-gle of 20 degrees.The Transient Rotor Stator (TRS)model which considering the transient interaction was set respectively at the “draft tube-runner”and “runner-adj ustable vane”interfaces.In this study, head-discharge curves were plotted and the head losses in the flow passages were calculated to reveal the mechanism of the unstable head variation.Results show that the unstable head-discharge performance is related to the vortex structure and accompanying loss.Compared with steady analysi

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介绍了一种汽车黏性耦合器试验机的开发，对试验机机械系统、测控系统、软件系统等进行了详细设计。并对车用黏性耦合器的转矩传递特性进行了试验研究。试验结果表明：该试验机性能稳定、操作简单、测试精度高，可对不同试件的“驼峰”特性、“回归”特性等进行准确评价，为该类产品的研发和改进提供了有力的试验支撑。
The development of an automobile viscous coupling test-bed was presented.Its mechanical system,control system and software system were designed in detail.The torque transfer characteristic of automobile viscous coupling was researched in this bed. Experimental results show that the test-bed is provided with stable in performance,simple operation,high measuring precision,and can evaluate “hump”characteristic and regression characteristic of viscous coupling accurately,which provides strong test support for product development and improvement.

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利用IGS的126个观测站双频GNSS观测资料和电离层层析成像技术,重构了2005-06-10电离层电子密度随纬度、经度和高度的三维时空变化规律.研究了低纬度地区电离层电子密度分布的周日变化规律和垂直结构特性,分析了赤道异常结构南北驼峰的形成、发展和消亡过程,讨论了影响电离层电子密度反演精度的因素.
3 D temporal-spatial variation regularity of ionospheric electron density were reconstructed by using the ionospheric tomography technique for the GNSS data of 126 stations on 10 June,2005.The diurnal variation regularity of ionospheric electron density distribution and variation characteristics of the ionospheric vertical structure in low-latitude region were investigated and the prosess of occurrence,development and disappearance of the equatorial anomaly structure were carefully analyzed.The factors that impact the accuracy of ionospheric electron density were discussed,and some suggestions were given for further investigation of ionospheric tomography technique.

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在简述长江口盐水入侵主要影响要素与特性的基础上,对三峡水库运行以来长江大通水文站年径流量、月径流量的变化规律进行了简析,发现长江下游仍呈现典型丰、平、枯水年特征,其季节变化规律也十分显著。同时对后三峡工程时代的长江口水源地盐水入侵特征进行了研究,结果表明,枯水期水源地咸潮入侵与其发生首日的大通水文站前6日日径流量相关性相对较好;影响期一般在农历九月至来年四月间,尤以二月最为严重;各月呈现出以初八和廿二为"双驼峰"型的氯化物质量浓度峰值分布特性。提出了进一步减轻长江口盐水入侵对上海水源地供水安全影响的建议,包括采取加强流域与区域信息资源共享、北支控制工程联建、长江口水源地(水库群)联动开发等措施。
Based on the main impact factors and features of saltwater intrusion in the Yangtze Estuary , the variations of the annual and monthly average runoff at the Datong Hydrological Station on the Yangtze River since the beginning of operation of the Three Gorges Reservoir were analyzed .The characteristics of typical wet years , normal years , and dry years are shown in the lower reaches of the Yangtze River with significant seasonal variations.Meanwhile, the features of saltwater intrusion into the water source zone in the Yangtze Estuary in the era after the beginning of Three Gorges engineering were studied .The results show that , in dry seasons , the saltwater intrusion into the water source zone had a relatively close correlation with the daily runoff at the Datong Hydrological Station six days prior to the first day on which the intrusion occurred .The impact of saltwater intrusion can usually be seen from September to the following April , and especially in February , according to

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基于鄂尔多斯盆地长8超低渗透油藏地质与流体特征，应用数值模拟方法和等效网格加密技术建立了分段多簇压裂水平井单井数值模拟模型。利用数值试井的手段，研究了分段多簇压裂水平井的渗流规律及影响因素。结果表明：分段多簇压裂水平井渗流主要分为6个阶段，且表现出双重介质的特性；井筒储集系数的大小决定着垂直径向流是否出现，驼峰峰值随表皮系数的增大而增大；主裂缝导流能力主要对前期和中期渗流阶段影响较大，裂缝半长对无因次压力和压力导数的影响较小；改造区渗透率对无因次压力和压力导数曲线位置及形状产生较大影响；应力敏感的存在会使无因次压力和压力导数曲线上移，但各个渗流阶段不会发生明显的变化。
Based on the geological and fluid proprieties of Chang-8 ultra-low permeability res-ervoir ,a single well numerical simulation model of segmented multi-cluster fractured hori-zontal is built by using the method of numerical simulation and the technology of equivalent local grid refinement (EQ-LGR) .Application of the model ,flow regimes and its affecting factors of segmented multi-cluster fractured horizontal well are studied by using numerical well test .The result shows that the segmented multi-cluster fractured horizontal well has six flow stages and show s the characteristic of double media .Whether the vertical radial flow ap-pears depends on the size of the wellbore storage coefficient .Hump peak increases with the increase of skin factor .Flow conductivity of main fractures mainly affects the early and mid-dle flow stages .Fracture half-length is less effect on the dimensionless pressure and pressure derivative .Permeability of simulated zone has great influence on the locations

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