Experimental study of shock-wave structure of supersonic underexpanded microjets

The structure of supersonic underexpanded room temperature air microjets is experimentaly studied. Microjets escaping from the nozzles with characteristic heights of 22.3 and 83.3 μm and widths of 2410 and 3900 μm respactacly with the Reynolds numbers of 640 and 2390. At these Reynolds numbers hot-wire anemometer measurements of mass flow pulsations are performed. It is shown that low value of the mass flow pulsations are corresponding with the high supersonic core length.