Results of experimental studies of the mechanism of evolution of plane and round macro- and microjet flows at low Reynolds numbers in a transverse acoustic field are discussed. New data on the jet development mechanism are obtained through hot-wire measurements and smoke visualization of the jet flow with the use of stroboscopic laser illumination of the jet at frequencies of the acoustic influence on the latter. In current research, more attention is paid to studying free macrojets because of their numerous applications in various fields of science and engineering. Nevertheless, there is considerable recent interest in studying microjets [1, 2], which is caused, in particular, by development of МEМS technologies. Microjets can be potentially used various processes, for instance, such as microcooling, jet burning, production of nanopowders, etc. Particular attention is given to the influence of the acoustic field on a microjet [3-5], which is important both for understanding the physics of the process and for practical applications of the phenomenon, for example, in aeronautical, space, chemical industry, etc. The work presented in this paper is aimed at elucidating the mechanism of evolution of macro- and microjets at low Reynolds numbers when subjected to a transverse acoustic field and at identifying the physical phenomena involved in this mechanism. A comparison of our previous studies [6-7] of macrojets under acoustic forcing with results of the current microjet investigations provide better understanding of various features of microjet evolution in an acoustic environment.
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7. Yu. A. Litvinenko, G. R. Grek, V. V. Kozlov, and G. V. Kozlov Subsonic round and plane macrojets and microjets in a transverse acoustic field // Doklady Physics, 2011, Vol. 56, No. 1, pp. 26–31.