Trapped gas pockets may cause severe operational problems in liquid piping systems. Experimental investigations of beat phenomena have been carried out in a laboratory apparatus. The transient event is initiated by rapid closure of a side-discharge solenoid valve. Predicted and measured results are compared and discussed. It is shown that the fully-developed beat is strongly attenuated by unsteady friction and not so by steady friction. This finding is important for safety analysis of hydropower plant. Air release is strongly recommended.
COBISS.SI-ID: 11272731