在选择管道的尺寸和强度、确定浪涌抑制设备的尺寸和规定系统操作规则时，必须考虑瞬态压力（水锤）。然而，分析人员经常忽略瞬态条件，尤其是在配电网等复杂系统中。计算机技术使人们能够在广泛的流动条件下分析配电系统，并且限制相对较少。本文强调，液压系统建模或表示的细节可能会对预测的瞬态条件产生关键影响。解释了与水锤有关的流体性质，并描述了瞬态条件的起源。作者驳斥了三个谬论:（1）最大稳态速度产生最大瞬态水头变化，（2）环形或分支结构缓解水锤，以及（3）如果一次喘振- 保护装置是好的，那么两个或更多更好。举例说明了过度简化物理系统或操作条件的危险。包括2个参考文献、图表。

Transient pressures (water hammer) must be taken into account when selecting the size and strength of pipe, sizing surge-suppression equipment, and specifying system operating rules. However, analysts frequently neglect transient conditions, particularly in complex systems such as distribution networks. Computer techniques make it possible to analyze distribution systems under a wide range of flow conditions and with relatively few restrictions. This article emphasizes that the details of how a hydraulic system is modeled or represented can have a critical impact on the predicted transient conditions. Fluid properties relating to water hammer are explained, and the origin of transient conditions is described. The author debunks three myths: (1) maximum steady-state velocities produce maximum transient head change, (2) looped or branched configurations alleviate water hammer, and (3) if one surge-protection device is good, then two or more are better. Examples are presented of the dangers of oversimplifying either the physical system or the operating conditions. Includes 2 references, figures.