Study on Liquid Pipeline Water Hammer and Protective Device with Gas Concentration

摘要

When pressure is low enough in pipeline the transported liquid vaporizes, and air can be let into the pipeline for various of reasons. After the pipeline is shut down, the air/vapor will gather and cavitation occurs. The existence of cavity in liquid pipeline is harmful when restarting the pipeline because the downstream equipments may not work properly. When the cavity collapse, the unsteady flow pattern in pipeline may be intensified due to the sudden increase of pressure and temperature, which may cause serious accidents. Analysis and calculation for the hydraulic status in gas concentrated liquid pipeline are presented in this paper using the rigid liquid column theory. A new type of protective device which automatically let in and release gas is designed by the author. The device is awarded the national patent of utility model.