Targeted Mach Wave Elimination
نویسنده
چکیده
منابع مشابه
Noise Measurements in Supersonic Jets Treated with the Mach Wave Elimination Method
We report noise measurements for perfectly expanded coaxial jets composed of a supersonic primary stream at velocity of 920 m/s and a co ow stream at conditions designed to prevent formation of Mach waves. Both the primary and secondary streams consisted of helium–air mixtures to simulate approximately the conditions of hot ows. The resulting sound eld was compared to that emitted by a sin...
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Experiments have characterized the acoustics of axisymmetric high-speed jets at a variety of Mach numbers and velocities and at pressure-matched, overexpanded, and underexpanded conditions. The effect of an annular secondary ow on noise emission was also investigated.The fully expanded jet velocity ranged from 630 to 920m/s and the fully expanded jet Mach number ranged from 1.27 to 1.75.The s...
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Supersonic jets emit noise to the outside in form of Mach waves which are long, straight and have about equal angles. Experiments done by Oertel sen. visualized clearly these Mach waves and he publicized moreover that such Mach waves exist also inside the jet. Experimental and theoretical studies in the past did not allow a complete understanding of the phenomenon up to now, wherefore the need ...
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