A Computational Study On The Powertrain Performance For The New Type Vehicles

Powertrain is an important component of a vehicle, moreover, its performance determines the vehicle functionality.Studying on the powertrain performance of the new type vehicle powertrain systems provides the basis for design and optimization of the powertrain system parameters.In this thesis, the theory of vehicle powertrain performance calculation and evaluation is used for two new types of powertrain systems.The calculation results indicate the advantages of the new sytems and give some recommendations for the application.Firstly,the thesis discussed the vehicle driving principle, performance,fuel economy, and some evaluating factors for the automobile performance.Secondly,the vehicle performance simulation software GT-DRIVE and the programming language VBA(Visual Basic for Application) were introduced.The simulation method using both the GT-DRIVE and VBA code was introduced,as well.Then the configuration,principle and power strategy of a hydraulic hybrid garbage pickup vehicle were discussed.The calculation modeling process of the hybrid vechile was described in details.In this basis, the performance and fuel economy of the hydraulic hybrid vehicle were programmed to analyze and assess the vehicle performance comprehensively.In addition a comparison between the original internal combustion engine powered vehicle and hydraulic hybrid vehicle was made.The calculation showed that the vehicle dynamic performance related to the initial pressure of the accumulator. In the specified driving cycle, the comprehensive fuel consumption reduced 24.71% compared with the original vehcile.Finally,a vehicle powertrain without traditional transmission was evaluated.For exploratory research on this power system's dynamic performance,a dynamic model was built with GT-DRIVE. The calculation showed that the maximum gradability was 28%, the maximum speed was 122.38km/h.This work showed that the theory and modeling method discussed in this thesis can be effectively used to study and evaluate the performance of new type vehicle powertrain systems.Hence this simulation method can provide guidance for the development of new type powertrain systems.