STUDY OF THE NOISE OF AN AIRCRAFT TWO-STROKE TWO-CYLINDER PISTON ENGINE
The results of studying the structure of the far sound field of a two-cylinder two-stroke in-line internal combustion engine of Rotax-582UL type are presented. Acoustic tests of the engine were performed during its operation as part of the power plant of MAI-890 light propeller aircraft under static conditions at Moscow aviation Institute local aerodrome. The tonal components caused by the engine operation are highlighted. Spatial, spectral, and energy characteristics of the engine sound field are obtained. The sound power of the overall tonal radiation of the engine is proportional to the engine speed in degree of 8.4. The presented directional factors and energy dependences can be used in the framework of an empirical model to estimate the community noise levels with similar piston engines.