Dynamic Stability of Pipes With Leakage

Dynamic stability is of concern in submerged piping configurations, which experience leakage flow such as nuclear reactor internals and heat exchangers. Based on actual industry problems it was noticed that leakage flow in piping slip joints could incur damaging vibration amplitudes. Slip joints are often designed into piping systems to accommodate static loads or thermal expansion. A simple geometry consisting of two cantilever pipes joined at their free ends with a slip joint was studied experimentally. In the experimental set up, fluid was pumped through the pipes, which were submerged in a tank. The experiment showed that an instability due to leakage does indeed exist for this configuration.