Analysis of middle range frequency vibration of aircraft reciprocating engine

The authors investigate into vibration characteristics of ASz-62IR-16E aircraft engine. The focus of empirical tests was on the middle frequency vibration range (1000-7000 Hz) that corresponds to vibrations caused by air-fuel mixture combustion process, and defining root mean square of the detected vibration and the amplitude − frequency function. The tests were conducted for seven characteristic engine speeds. Vibrations were measured along three axes of local Cartesian coordinate system. Results indicate directions, frequency ranges and scale of strongest vibrations. The work is a part of identification tests and is intended to provide input for redesign of the engine ignition system. In particular, ASz-62IR-16E engine in test bed, coordinate system for the experiment − designation of axes, sensors mounted on the engine block, comparison of root mean square of full detected range of vibrations (RMS), spectral analysis of vibration for characteristic engine speeds, vibration peaks for all engine speeds, vibrations attributable to combustion process are presented in the article.