Observation and study of cavitation in closed flow system

Abstract

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.

Cavitation phenomenon is one of the most problems affecting the performance and efficiency of hydraulic machines and causes erosion damage to the machine. In the last decades many of researches have been focused to eliminate and minimize the cavitation occurrence in hydraulic machines. A special water tunnel was designed and constructed in order to obtain adequate information about incipient, developed and breakdown cavitation in a closed flow system, and hence use it as criteria to evaluate the point of cavitation inception in centrifugal pumps. The cavitation has been obtained using different bodies of circle, triangle and rectangular shapes fixed at up-steam of the tunnel test section. The effects of flow velocity, discharge and cavitation source shape against the cavitation degree were obtained. The relationship between the flow velocity at throat of test section and cavitation inception number was obtained.