Structure of subsonic plane microjets

Results of experiments aimed at studying subsonic microjets escaping from a plane nozzle are reported. The Reynolds numbers based on the nozzle height and mean flow velocity at the nozzle exit are varied from 27 to 139, whereas the nozzle size is fixed at 83.3 × 3823 µm. The test gas is air at room temperature. The distributions of velocity and velocity fluctuations along the jet axis and in the lateral and transverse directions are determined. The fact of the laminar–turbulent transition in the jet is detected. The data obtained are compared with theoretical predictions for laminar plane jets. The experimental and theoretical data are found to be in good agreement at the laminar segment of the microjet.