FLOWS GENERATED BY THE IMPINGEMENT OF A JET ON A ROTATING SURFACE .1.BASIC FLOW PATTERNS

The results of an experimental study of the flow field resulting from the interaction between an impinging jet and a rotating disk are prese nted. The resulting flow configuration has applications in turbomachin ery, for example, to intensify the local heat transfer at turbine disk s. The experiments cover separate measurements of the disk-wall pow, t he jet flow and interaction between the two. The flow patterns are inv estigated over a range of jet Reynolds numbers Re-jet = 0.66 . 10(4) - 6.80 . 10(4) (based on jet diameter) and disk Reynolds number Re-disk = 3.4 . 10(5) - 6.2 . 10(5) (based on impingement radius), achieved b y varying the jet nozzle diameter, jet flow rate, rotational disk spee d and the impingement radius. The measurements included the depth of j et penetration into the wall boundary layer the travel distance of the jet against the direction of disk rotation, and the turbulent and mea n velocity distribution. Another objective of this study concerns the type of flow at the impingement region (jet dominated flow or rotation dominated flow) and the conditions for the transition from one to the other. in the first part of the study, the flow structure of the jet and disk flows as well as the three-dimensional flow fields resulting from the interaction ara presented.