Description: The article describes design schemes and features of single-circuit aircraft gas turbine engines from the point of view of acoustic vibration diagnostics. It was noted their advantages in comparison with double-circuit gas turbine engines. Under this scheme, the problem of choosing the most informative points for measuring vibration signals from rotor supports to the outer casing is relatively simple to solve. To solve the problem of a more detailed diagnosis of the technical condition, it is necessary to make as many measurements as possible at different points on the aircraft gas turbine engines housing. A brief analysis and evaluation of modern diagnostic information systems that work in a limited frequency range and use a limited number of vibration sensors (one or two) as primary information is given. The inability of these systems to track defects in components and assemblies at the initial stage of their development. In order to optimize the program for obtaining vibration information, vibration measurement time, and minimizing the resource consumption of a gas turbine engines and aviation fuel, a methodology has been developed for identifying vibration measurement points to determine the technical condition of aircraft power units using a narrowly directed vibration transducer. The direct power connection between the rotor bearings and the outer casing of the TV2117 and TV3-117 engines installed on the Mil MI-8T helicopter was investigated. The key points for obtaining vibration information on these gas turbine engines are determined, taking into account the presence of a free turbine, using a narrowly directed vibration transducer: on the main drive assembly, compressor, turbine, and gearbox. The vibrations parameters are often used as a health indicators for aircraft gas turbine engines. That is why the most obvious way to prevent any damages of engine structure is to provide a spectral analysis. The best way of developing this method will be implementing in complex diagnostic system that will indicate further behavior of engine structures.
Keywords: aircraft, engine vibration, rotor, vibration measurement, turbocharger, gearbox
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