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With energy conservation and pollutant emission of paramount importance in today's society, it has emphasized the need for aerodynamic drag reduction in the automotive sector. Innovative ideas, better visualization, reduced time in the design process, and cost effective “computational testing” is all put together is the use of Computational Fluid Dynamics. In the present study the analysis of the complex flow structure around a bluff body is presented. The importance and advantages of the numerical simulations are discussed. The quality of the mesh is of great importance and the types of grid generation schemes are presented here. The shape of the rear of the body has a marked influence on the body drag. The importance of the back slant angle and its effect on the flow structure and in turn its effect on the drag force of the body is presented.

A zero dimensional computer code was developed to predict the performance of an spark ignition internal combustion fuel inducted engine. The code can be used to predict engine performance for automotive and racing applications. Expressions for turbulent flame speed were developed based on turbulent flame intensity and cylinder geometry. This turbulent flame intensity varies across the RPM span and was formulated based on a semi-empirical correlation study in a joint experimental/computational effort by the investigator which utilizes extensive dynamometer experimental results for automotive engine applications. In-cylinder wall temperatures are determined based on a newly developed empirical correlation which accounts for the influences of air-fuel ratio, compression ratio, spark timing and coolant temperature. Auto-ignition or knock is also predicted.

This study presents a computationally efficient numerical model that accurately predicts complex spray distribution and spray penetration for a direct injection compression ignition engine configuration. Experimental data obtained from available literature is used to construct a semi-empirical numerical model. A modified version of a multidimensional computer code KIVA-3V is used for the computations, with improved sub-models for varying mean droplet diameter, varying injection velocity and drop distortion and drag. Results show good agreement with the published in-cylinder experimental data for a Volkswagen 1.9 L turbo-charged direct injection under actual operating conditions.