IMPINGING JET STUDIES FOR TURBULENCE MODEL ASSESSMENT .1. FLOW-FIELD EXPERIMENTS

The paper reports an extensive set of measurements of a turbulent jet impinging orthogonally onto a large plane surface. Two Reynolds number s have been considered, 2.3 x 10(4) and 7 x 10(4), while the height of the jet discharge above the plate ranges from two to ten diameters, w ith particular attention focused on two and six diameters. The experim ent has been designed so that it provides hydrodynamic data for condit ions the same as those for which Baughn and Shimizu [ASME J. Heat Tran sfer 111, 1096 (1989)] have recently reported Nusselt number data (at Re = 23 000). In both experiments, before discharge, the air passed al ong a smooth pipe sufficiently long to give fully developed flow at th e exit plane of the jet-a feature that is helpful in using the data fo r turbulence-model evaluation. Hot-wire measurements have been made wi th pipes of nominally one-inch (26 mm) and four inches (101.6 mm) diam eter. Data are reported of the mean velocity profile in the vicinity o f the plate surface and also of the three Reynolds-stress components l ying in the x-r plane. Computational results reported in a companion p aper [Int. J. Heat Mass Transfer 36, 2685-2697 (1993)] indicate a good degree of internal consistency between the mean and turbulent field d ata in that models predicting the mean flow poorly (or well) also pred ict the turbulence data poorly (well).