Analysis of Waterhammer Induced by Steam-Water Counterflow in a Long Horizontal Pipe

Abstract

Improved analytical models have been proposed that can predict the lower and upper limits of thc waterhammer region for given flow conditions by incorporation of recent advances made in the understanding of phenomena associated with the condensation-induced waterhammer into existing methods. Present models are applicable for steamwater counterflow in a long horizontal pipe geometry. Both lower and upper bounds of the waterhammer region are expressed in terms of the 'critical inlet water flow rate' as a function of axial position. Waterhammer region boundaries predicted by present and typical existing models are compared for particular flow conditions of the waterhammer event occurred at San Onofre Unit 1 to assess the applicability of the models examined. The result shows that present models for lower and upper bounds of the waterhammer region compare favorably with the best performing existing models.