【作者】 刘云芳；

【导师】 阎庆绂；

【作者基本信息】 太原理工大学 ， 水力学及河流动力学， 2003， 硕士

【摘要】 在许多行业的动力系统运行中，都出现过由于各种意外原因而使系统进入失控工况的事例。失控工况发生时常伴随有瞬变现象的出现，而系统中的瞬变将会不同程度地对系统造成一定的危害，轻则使设备损坏，系统不能正常工作，重则造成停产，人员伤亡等严重后果，所以失控工况尤其是失控工况发生时瞬变强度的预防和控制应引起足够重视，并找出能够控制失控工况的瞬变强度的方法，用于指导生产实践，使运行系统不发生瞬变现象或即使是瞬变现象发生了也能将其危害降到最低，避免经济损失。据此，本文对典型的失控工况进行了实验研究和理论分析，主要内容和结论如下： 1．典型失控工况特性的实验研究。 文中根据动力系统的实际情况，归纳了六种典型的失控工况，并根据实验条件在保证安全的前提下，对带负荷启动经短暂稳定后停泵的失控工况特性进行研究，得到了一批研究成果。 1)泵的进出口压头和流量的瞬变规律； 2)管系中间压头瞬变规律； 3)管系出口压头和流量瞬变规律； 4)泵轴转矩变化规律；太原理工大学硕士学位论文2.论述分析了失控工况可能出现的基本特性。 l)失控工况可能出现两种后果:基本无瞬变或发生弱瞬变; 发生强瞬变流动。 2)本文研究的条件下，带负荷启动泵在一定条件下出现强 瞬变，负荷停泵基本无瞬变或发生弱瞬变。3.分析了带负荷启动和负荷停泵两种失控工况的特性，它们是: l)时间特性，包括:泵出口无压和无流量输出时间;管系 中部和出口处负压与倒流时间;泵出入口、管系中部和 出口处压头振荡时间;泵出口、管系出口流量振荡时间; 2)瞬变压头和流量的频率和振幅特征:泵出入口、管系中 部和出口处压头的振荡频率和幅值;泵出口和管系出口 处流量振荡频率和幅值; 3)泵轴转矩变化特征;4.提出了系统深长比的新概念。 1)定义系统上游水深(或压头)与管系长度之比为系统的 深长比; 2)计算分析了带负荷启动工况下，深长比与瞬变参数的关 系; 3)给出了强瞬变和弱瞬变的深长比范围;5.提出了失控工况的控制方法和途径。 1)控制系统深长比可以控制系统失控工况的瞬变强度。 2)在本文研究条件下，深长比大于6.25和小于0.19时发 生强瞬变，深长比大于0.19而小于6.25时基本不发生太原理工大学硕士学位论文瞬变或发生弱瞬变;3)文中给出的深长比与瞬变参数关系及得到的实验成果 图，可用于指导失控工况特性的理论研究、工程设计和系统的运行调节。更多还原

【Abstract】 There have many examples caused by the unexpected reasons that can make the system into the runaway operating mode in the operation of the power system in many industries. The runaway operating modes occur usually accompanied with the transient phenomena. The transients will do harm to the system in some degree. The lighter will make the equipments break down which make the system can not work normally; the heavier will cause the grievous consequences such as the stopping of the production or the injuries and deaths. So the runaway operating mode particularly the prevention and control of the transient intensity must been paid the most attentions. And it is important to find out the methods that can control the transient intensity when the runaway operating modes occur and can be used to conduct the production in order that there have not the transient phenomena when the system is working or it will cause the least harms that can avoid the economic loss even if the phenomena occurred.On these grounds, I have made the experimental researchand theorical analyse about the typical runaway operating mode. The main contents and conclusions are:1. The experimental research on the characteristics of the typical runaway operating mode.There have induced six kinds of the typical runaway operating mode according to the actual conditions of the power system. And under the condition that assure the safety, the article made the research of the runaway operating mode’ characteristics under the condition that stopping the pump after brief steady with starting with load, and got a batch of achievements:1) The transient law of the pressure and flow in the import and exit of the pump;2) The transient law of the pressure in the middle of the pipeline;3) The transient law of the pressure and flow in the import and exit of the pipeline;4) The changing law of the rotating moment of the pump.2. Discuss and analyse the basic characteristics that may appear in the runaway operating mode.1) The runaway mode will bring two consequences: the first is there have not transient phenomena or there have only weak transients , the second is there havethe strong transients.2) Under the research of the article, there may appear the strong transients in starting the pump with load, there have not transients or have only weak transients in the stopping with load. 3. Analyse the two kinds of runaway operating mode’ characteristics. The two modes are the starting with load and the stopping with load. The characteristics are:1) The characteristics of time. Including:The time without pressure and flow output in the exit of the pump; The time with negative pressure and flow backwards in the middle and exit of the pipeline; The time of pressure’ vibration in the import and exit of the pump , the middle and exit of the pipeline ;The time of the flow’ vibration in the exit of the pump and the pipeline.2) The frequency and extent characteristics of the transient pressure and flow.The frequency and extent of the pressure in the import and exit of the pump, the middle of the pipeline and the exit of the system; the frequency and extent of the flow in the exit of the pump andthe pipeline.3) The changing characteristics of the pump’ rotating moment.4. Put forward the new conception of HL.1) Define the ratio between the depth in the upper reaches (or pressure) and the length of the whole pipeline as HL;2) Count and analyse the relation between the HL and the transient parameters under the mode of starting with load;3) Give out the range of the HL that can distinguish the strong transients from the weak transients.5. Put forward the methods and way that can control the runaway operating mode’ characteristics.1) The transient intensity of the runaway operating mode can be controlled by controlling the HL of the system;2) Under the research of the article , there will occur the strong transients when the HL ≥ 6.25 and ≤ 0.19,while there will have not transients or have the weak t更多还原