cavitation characteristics during startup process of a condensate pump with splitter blades

The present study aim s to describe characteristics of cavitation du ring the startup process of a condensate pump. the pump is featured by an impeller equipped with five splitter blades. a computational fluid dynamics (cfd) work w as conducted to plumb the evolution of cavitation in the pump. effect of the volumetric flow r ate on instantaneous cavitation patterns as the rotational speed of the pump increase d was analyzed . the results show that high resistance to cavitation of the pump depends greatly on large area of the impeller eye, which i s related to the deployment of th e splitter blades . the splitter blades are insignificantly affected by cavitation. during the startup process, both the pump head and the pump efficiency vary drastically , which is insensitive to the flow rate . a t a net positive suction head npsh of 2.0 m , high flow rates are responsible for intensified cavitation. h igh volume fraction of cavitation arises near the inlet of long blades . as the rotational speed increases, the evolution of cavitation is featured by intermittency and diversified cavity patte rns. furthermore, t he sum of the volume fraction of cavitation fluctuates with continuously increasing rotational speed.