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RESEARCH TO IMPROVE POWERTRAIN NOISE, VIBRATION AND HARSHNESS CHARACTERISTICS

The paper presents a research algorithm consisting of: a developed methodology for selection of target values for natural frequencies and localization of vibration-loaded area of the powertrain based on calculation (simulation) and experimental research of resonant frequencies of the powertrain in operating modes and disturbances from two types of roads, calculation and experimental methodology for research of natural frequencies and oscillation modes of the powertrain, developed methodology for powertrain design refinement in terms of natural frequencies up to compliance with the target values and reduction of structural noise. Results of calculation and experimental research of resonant frequencies of the powertrain in operating modes and in case of disturbance from two types of roads are provided. There is also a justification given for selection of the target value for the powertrain natural frequency. Calculation of powertrain natural frequencies and oscillation modes was performed using the finite element method; experimental verification of the calculation was carried out as well. Using the verified calculation (simulation) model, design changes were introduced to reach the target values for natural frequencies and to reduce structural noise. Comparative calculation studies of the frequency response confirming the efficiency of the design changes are carried out.