Study on Automotive Driveline System with Torque Converter Clutch under Harmonically Varying Normal Load

In this research project, an Automotive Driveline System with Torque Converter
Clutch under effects of a harmonically varying normal load on transient responses of
a 2-Degree Of Freedom torsional system is studied. An inunediate application of this
study is the slipping torque converter clutch that is employed in automotive driveline
system. The purpose of Torque Converter Clutch is to transmit rotating power from
the prime movers (internal combustion engine) to the rotating driven load. Up to 10
percent of the engine energy is wasted by torque converter slipping caused by
negative slope introduced by substantial stick slip motion. Investigation on key
parameters that control the clutch engagement rate and pronounce the stick slip
motion could further attenuate such motion. The objectives of this project is to
develop its mathematical model, the system is supposed to be 2-Degree of Freedom
torsional system with non-linear dry friction. Under this mathematical model, the
governing equation that represents the dynamics of the system and non-linear time
varying dry friction formulation is established. Then the development of MA TLAB
progranuning to simulate the dynamics of the system is established. From the
numerical simulation in MATLAB programming, transient responses including pure
slip and stick slip transient response of the system under a harmonically varying load
and sinusoidal torque excitation will be studied computationally. The effects of
saturation friction torque, mean torque and engine inertia on clutch engagement rate
are found significant in pure slip transient response. Furthermore, the effects of
kinetic friction, saturation friction torque and phase lag on the stick-slip transient
response Gudder) influence the dynamics of the system by the introduction of stick
slip motion.