Application of dual mass flywheel on internal combustion engines and its effects on performance of vehicle powertrain system

The automotive sector must have a strong research and development structure and knowledge to meet the demands of performance, comfort, economy and environmental protection. Therefore the design of the system elements that provide the transfer of power from the engine to the wheels in a vehicle and the dynamics of the power transmission system are important study topics. The flywheel is a part that reduces the speed fluctuations on the crankshaft in the internal combustion engines. Besides, it is the first element of the power transmission system. The dual mass flywheel is simply the form that single mass flywheel is divided into two parts and these parts are combined with a spring damper system. It is considered the dual mass flywheel that generally used in diesel engines has the positive effects on the dynamic of power transmission system according to single mass flywheel. In this study after giving information about the requirement of flywheel in machines and the structure of dual mass flywheel, the power transmission systems that used single and dual mass flywheel are compared in terms of the system natural frequency (resonance) and clutch dynamics. For this purpose, mathematical models of both power transmission systems were formed after the necessary theoretical information was explained. These models were solved in Matlab environment for all gear situations and both systems were compared in terms of resonance and clutch dynamics. In addition, the effects of changes in some parameters of the dual mass flywheel on the natural frequency of the powertrain were also investigated. It was determined that the dual mass flywheel shifted the engine speed at which the resonance occurred for all gears away from the idle speed and kept away from the engine's working range. In terms of clutch dynamics the clutch times are almost the same in both systems. However, in the system where the dual mass flywheel is used, the clutching process is performed more smoothly. According to the results, it can be said that the dual mass flywheel has positive effects on the vehicle power transmission system's performance.