Research On Vibration Absorption Of Variable Inertia Flywheel Based On Magnetorheological Technology

In the powertrain system,the crankshaft of the engine,the spindle of the machine or other gears are in operation,and will cause torsional vibration due to manufacturing error,installation error and working environment.This vibration will not only produce noise but also reduce the transmission accuracy,even will cause the drive shaft fatigue failure,causing serious consequences.The installation of a torsional damper in a powertrain system is an effective way to eliminate and isolate torsional vibrations.With the development of powertrain to high speed and heavy load,the torsional vibration of the transmission system is more and more intense,and a new torsional vibration reduction technology is urgently needed.The traditional torsional damper is difficult to meet this need.At present,the study of torsional damper is mainly through the adjustment of the elastic element and the damping element parameters to achieve the suppression of torsional vibration,but this adjustment can not be adaptive adjustment.In recent years,the variable inertia flywheel have been used to suppress of linear vibration,which have a better effect.However,it is difficult to apply variable inertia flywheel to torsional vibration suppression.There is an urgent need for a simple structure,low energy consumption,easy to control the variable inertia flywheel.Magnetorheological fluid is a intelligent materials,which is fast response and controllable.Magnetorheological damper has the advantages of short response time,adjustable damping and less energy consumption.In this paper,a new semi-active variable inertia flywheel is proposed based on the magnetorheological technology,which not only has the characteristics of passive inertia flywheel structure,but also can realize different working conditions.The results show that it is of great significance to solve the problem of torsional vibration of power transmission system by theoretical analysis and experiment.The main work of this paper has the following aspects:(1)The vibration principle of the variable inertia flywheel is analyzed,and the rotary two degree of freedom dynamic model with dynamic vibration absorber is established.The influence of the parameters and inertia of the dynamic vibration absorber for the vibration of the main system is analyzed.The flywheel moment of inertia is achieved when the vibration absorption effect is optimal under different excitation.(2)A design method of variable inertia flywheel based on magnetorheological technology is proposed.The mathematical model of the moment of inertia and magnetorheological damping force and rotational speed is obtained by mechanical analysis.Finally,the relationship between the damping force,spring stiffness and flywheel moment of inertia of magnetorheological damper is analyzed.(3)The multi-objective genetic algorithm is used to optimize the design of inertia flywheel,and the key structure size is determined.Based on the optimization of the parameters,the theoretical moment of inertia model of the magnetorheological inertia flywheel is established,and the rotary two degree of freedom dynamic model is established by combining the single degree of freedom torsion system.Finally,the effect of the magnetorheological inertia flywheel on the suppression of the main system and the control strategy are analyzed.(4)A magnetorheological inertia flywheel prototype was developed and the performance of the prototype was tested.The relationship between the damping force and the velocity is measured under the sinusoidal excitation of the magnetorheological fluid damper.The stiffness of the spring is measured and the actual stiffness of the spring is obtained.The mathematical model of the moment of inertia,current and speed based on the experiment was established.The relationship between the moment of inertia of the flywheel and the piston displacement is measured by the three wire pendulum method.The relationship between the moment of inertia and the rotational speed and the relationship between the magnetorheological inertia flywheel and the piston displacement are tested.The magnetorheological inertia flywheel inertia model is verified by the dynamic test platform.The validity of the inertia model of the magnetorheological inertia flywheel is verified.