Impact of Using Chevrons Nozzle on the Acoustics and Performances of a Micro Turbojet Engine

This paper presents a study regarding the noise reduction of turbojet engine, in particular jet micro engine. The results measurement campaign are presented followed by performances analysis which is based on measured data test bench. Within tests, beside baseline nozzle other two nozzles with chevrons were tested and evaluated. First type foreseen eight triangular chevrons, length being L = 10 percentages from equivalent diameter an immersion angle I 0 deg. For second maintained, only number increased at 16. engine has been four different regimes speed. monitored measuring fuel flow, temperature front turbine, intake air compression ratio, propulsion force before compressor. In addition, during testing, vibrations axial radial direction indicate normal functioning chevron testing. Regarding noise, it was concluded that low doesn’t any when using nozzles, while high overall 2–3 dB(A) achieved. performances, decrease ratio flow achieved also drop few percent force.