TIP CLEARANCE SENSITIVITY OF CENTRIFUGAL PUMPS WITH SEMI-OPEN IMPELLERS

摘要

Using experimental data of 14 pumps with different semiopenrnimpellers, an attempt has been made to predict therndecrease of head due to increased tip clearance, i.e. the gaprnbetween casing and impeller blades. After defining arncharacteristic number, a quantitative relation between tiprnclearance sensitivity and geometry of the impeller was found.rnRecommandations are given for the impeller design concerningrntip clearance sensitivity. However, measurements on furtherrnpumps will be required before the characteristic number can bernused generally.