Abstract Cracks caused by water hammer are one of the most common destructive forms in water supply pipeline systems. Unlike developed cracks, incipient cracks are not likely to be found, as they do not leak under normal running conditions. However, as a potential threat, the incipient cracks may rapidly develop under severe water hammer effects. To investigate the features of incipient cracks and their effects on water supply running conditions, an experimental platform was established, equipped with an upstream tank, a long steel pipeline, a downstream valve, some incipient crack physical models and several high-accuracy pressure sensors. In experimental observation and recorded data analysis, elemental features of incipient cracks are identified and a numerical simulation model was established accordingly. Furthermore, several parameters including crack scale and location were investigated based on various cases studies. Both crack scale and location have significant effects on water hammer intensity.

中文翻译：

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管道系统瞬态条件下初始裂纹的间歇性泄漏现象†

摘要 水锤裂纹是供水管道系统中最常见的破坏形式之一。与已发展的裂纹不同，早期裂纹不太可能被发现，因为它们在正常运行条件下不会泄漏。然而，作为潜在的威胁，初期裂缝可能会在严重的水锤效应下迅速发展。为研究初始裂纹的特征及其对供水运行条件的影响，搭建了一个实验平台，配备了上游水箱、长钢管道、下游阀门、初始裂纹物理模型和多个高精度压力传感器。通过实验观察和记录数据分析，确定了初始裂纹的基本特征，并据此建立了数值模拟模型。此外，基于各种案例研究，研究了包括裂纹规模和位置在内的几个参数。裂纹规模和位置对水锤强度都有显着影响。