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前言在事故停泵过程中,由于水锤作用引起的最低和最高压力,以及机组转子的最高逆转速度等最不利参数及其出现的时刻是确定管道设计压力、选配管道阀件和水锤防护措施的主要依据。所以在泵站设计中能否合理地解决事故停泵水锤问题,对于节省工程投资和运行费用、以及保证安全运行等都有十分重要的意义。尤其对于高扬程,大流量和长管道的泵站,其效果尤为显著。关于事故停泵过程中最不利参数的计算,通常有数解法、解析法和图解法等三种。它们虽然具有较高的精度,但是,计算方法繁冗,费时甚多。尤其在泵站的初步设计中,由于许多因素都处于进行初选,试算和方案比较阶段,采用上述方法尤感不便。虽然从六十年代开始国外已经利用电子计算机解析泵站水锤问题,但在我国至今尚不够普及。美国工程师 J、帕马金的事故停泵过程中各主要参数的计算图是根据许多计算结果归
Preface The most unfavorable parameters due to the minimum and maximum pressure caused by the water hammer and the maximum reverse speed of the rotor of the unit during the process of an accident pump stop and the moment when it occurs is to determine the design pressure of the pipeline. Optional piping valves and water hammer protection The main basis for the measure. Therefore, it is very important to solve the water pump hammer problem in the pump station design reasonably to save the project investment and operation cost as well as ensure the safe operation. Especially for high lift, high flow and long pipe pumping station, the effect is particularly significant. On the accident pump stop the most unfavorable parameters of the calculation, usually a number of solutions, analytical methods and graphical method of three. Although they have high precision, however, the calculation method is burdensome and time-consuming. Especially in the preliminary design of pumping stations, the above method is particularly inconvenient because many factors are in the stage of preliminary election, trial calculation and program comparison. Although foreign countries have used electronic computers to analyze the problem of water hammer in pumping stations since the 1960s, it is still not enough popular in our country. American engineer J, Parmakin’s accident during the pump stop the calculation of the main parameters of the graph is based on many calculations