Litvin R. Improvement of the Operational Properties of an Automobile Transmission Using a Dual-Mass Flywheel

The object of research is oscillation processes in the drive of the car equipped with a dual-mass flywheel (DMF), on various operating modes. Research methods. The methods of analytical mechanics, numerical methods for solving differential equations, experiment planning and processing of measurement results are used in the work. Scientific novelty of the obtained results: the classification of the reasons of failure of a DMF is proposed and their influence on the operational properties of the car transmission is found; based on generalized dynamic models of the car drive mathematical and simulation models of the oscillation processes in a transmission equipped with a DMF, taking into account elastic-dissipative properties and change of the drive structure, at idling, moving the car from rest, and its acceleration are developed in the MatLab Simulink environment; the influence of design parameters of the transmission and DMF on the loading of their sections at the modes of idling, moving the car from rest, and its acceleration is investigated; it is found that the main reason for the failure of the elastic-dissipative system of a DMF, and hence the loss of transmission workability, is the fatigue failure of the elastic sections of a DMF, caused by their cyclic loading; dynamic, mathematical, and simulation models in the MatLab Simulink environment of the drive of a hybrid car with the combined power unit and DMF in the car acceleration stage taking into account elastic-dissipative properties of transmission components and simultaneous work of the electric motor and internal combustion engine (ICE) are developed; constructive changes and an adaptive control algorithm for a DMF at various modes of the car movement aimed at increasing the lifetime of the DMF elastic components and, as a result, improving the operational properties of the car transmission are proposed. The practical significance of the obtained results lies in the development of simulation models for the analysis of the oscillation processes in the car drive to match the parameters of the DMF and other transmission components; the structure of the control system and the operational algorithm of the adaptive DMF at different modes of the drive operation and car movement to reduce the probability of fatigue failure of the elastic sections of the flywheel; design of the adaptive DMF, which provides blocking the relative rotation of the primary and secondary masses of the DMF in the car moving at constant speed modes, which significantly reduces the number of load cycles of the elastic-damping system, and therefore increases the lifetime of the DMF.