What is the term for a pressure surge caused by a sudden stop or change in direction of fluid flow?

The term for a pressure surge caused by a sudden stop or change in direction of fluid flow is commonly referred to as water hammer. This phenomenon occurs when a fluid in motion is forced to stop or change direction abruptly, resulting in a shock wave that travels through the fluid. Water hammer is particularly significant in piping systems where sudden valve closures or pump shutdowns occur.

When the fluid inertia is disrupted, the momentum of the moving liquid creates pressure fluctuations, which can manifest as noise, vibration, and even physical damage to the piping infrastructure. Understanding and mitigating water hammer is crucial in hydraulic systems to ensure their longevity and safe operation.

Other options, while related to fluid dynamics, either refer to different concepts or are not as specific to the surge caused by abrupt changes in flow.