EFFECTS OF INTERACTION BETWEEN ADJACENT FREE-SURFACE PLANAR JETS ON LOCAL HEAT-TRANSFER FROM THE IMPINGEMENT SURFACE

Experiments have been conducted to obtain single-phase, local convection heat transfer coefficient distributions along a constant heat flux surface experiencing impingement by two, planar, free-surface jets of water. Nozzle widths and nozzle-to-heater separation distances were fixed at 5.1 and 89.7 mm, respectively, while two nozzle-to-nozzle pitches (81 and 51 mm) were considered. The ratio of impingement velocities for the two nozzles, V*, was varied from 0.47 to 1.0. Interacting wall jets created by the impinging jets yielded a strong upwelling of spent flow (an interaction fountain), beneath which convection coefficients were comparable to those associated with the jet impingement regions. With decreasing V*, impingement heat transfer coefficients beneath the weaker jet were reduced by the effects of crossflow imposed by the stronger jet.