Investigation on the flow in a rotor-stator cavity with centripetal through-flow
Hu, B. and Brillert, D. and Dohmen, H.J. and Benra, F.-K.
12TH EUROPEAN CONFERENCE ON TURBOMACHINERY FLUID DYNAMICS AND THERMODYNAMICS, ETC 2017
Daily and Nece distinguished four flow regimes in an enclosed rotor-stator cavity, which are in dependence on the circumferential Reynolds number and dimensionless axial gap width. A diagram of the different flow regimes including the respective mean profiles for both tangential and radial velocity was developed and the moment coefficients for the different flow regimes have been correlated. In centrifugal pumps and turbines, the centripetal through-flow is quite common from the outer radius of the impeller to the impeller eye, which has a strong influence on the radial pressure distribution, axial thrust and frictional torque. The influence of the centripetal through-flow on the cavity flow with different circumferential Reynolds numbers and dimensionless axial gap width is not sufficiently investigated. It is also quite important to convert the 2D Daily&Nece diagram into 3D by introducing the through-flow coefficient. A test rig is designed and built up at the University of Duisburg-Essen. The design of the test rig is described. The impact of the above mentioned parameters on the velocity profile, pressure distribution, axial thrust and frictional torque are presented and analyzed in this paper. Part of the 3D Daily&Nece diagram is also organized in this paper. Copyright © by the Authors.