Heat Load Simulation Research Of Dry-DCT During Strarting With Two Clutches

Dual Clutch Transmission (DCT) is a new type of automatic transmission, which isevolved from Automated Manual Transmission (AMT). It not only inherits theadvantages of simple structure, high efficiency and low cost from AMT, but alsoprovides the ability of power shifting of Automatic Transmission (AT) and ContinuouslyVariable Transmission (CVT) that can improve the dynamic performance, fuel economyand emission performance of vehicle. DCT has a powerful market competitiveness andfavorable foreground of broad market. Thus, aiming at the key technologies of DCTsystem, researching and mastering the key technologies, have great practicalsignificance to promote the development and technological progress of automotiveindustry of china.In this thesis, the study of key technology of temperature rise of the DCT dual dryclutch during starting of vehicle is carried out relying on a project supported by theNational Natural Science Foundation of China “Research of the durability design theoryand control methods of dual dry clutch”. Based on the computer simulation and finiteelement technology, it has to complete the heat load research of dry-DCT during startingwith two clutches. The main works as follow:①Based on the structure and working principle of DCT system, in order toreducing the sliding friction work of single clutch during the starting process of vehicle,a control strategy of starting with two clutches, which was based on the control ofstarting with a constant engine speed, was analyzed and proposed.②The dynamical simulation model of starting with two clutches and the slidingfriction work calculated model were both established in Matlab/Simulink. Slidingfriction work curves of DCT dry dual clutch in several starting conditions werecalculated.③Based on the heat transfer theory, the modes of heat transfer of the DCT drydual clutch were analyzed. According to the simulation results in several startingconditions in Matlab/Simulink, the initial conditions and boundary conditions forthermal analysis of clutch were acquired. The transient temperature fields, thermaldeformations and thermal stress fields of the dry dual clutch in concerned startingconditions were simulated by using Ansys software.④The factors that influence the temperature rise of the dry dual clutch were analyzed. The orthogonal test was taken to research the influence trend and extent of thefactors above. According to the conclusion above, several measures for reducingtemperature rise were summarized.