IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) e-ISSN: 2278-1684,p-ISSN: 2320-334X, Volume 7, Issue 5 (Jul. - Aug. 2013), PP 28-35 www.iosrjournals.org www.iosrjournals.org 28 | Page CFD Simulation for Flow over Passenger Car Using Tail Plates for Aerodynamic Drag Reduction R. B. Sharma 1 , Ram Bansal 2 1 HOD, Mechanical Engineering Department, RJIT BSF ACEDEMY Tekanpur 2 Research Scholar, Department of Automobile Engineering, RJIT BSF ACEDEMY Tekanpur Abstract: This work proposes an effective numerical model based on the Computational Fluid Dynamics (CFD) approach to obtain the flow structure around a passenger car with Tail Plates. The experimental work of the test vehicle and grid system is constructed by ANSYS-14.0. FLUENT which is the CFD solver & employed in the present work. In this study, numerical iterations are completed, then after aerodynamic data and detailed complicated flow structure are visualized. In the present work, model of generic passenger car has been developed in solid works-10 and generated the wind tunnel and applied the boundary conditions in ANSYS workbench 14.0 platform then after testing and simulation has been performed for the evaluation of drag coefficient for passenger car. In another case, the aerodynamics of the most suitable design of tail plate is introduced and analysedfor the evaluation of drag coefficient for passenger car. The addition of tail plates results in a reduction of the drag-coefficient 3.87% and lift coefficient 16.62% in head-on wind. Rounding the edges partially reduces drag in head-on wind but does not bring about the significant improvements in the aerodynamic efficiency of the passenger car with tail plates, it can be obtained. Hence, the drag force can be reduced by using add on devices on vehicle and fuel economy, stability of a passenger car can be improved. Keywords: Aerodynamic Drag, Coefficient of Drag, Coefficient of Lift,Tail Plate, Wind tunnel simulation, ANSYS FLUENT, Generic passenger car, CFD. I. Introduction A few years ago when fuel crisis was not a problem, cars were mainly designed for high-speed manoeuver, comfort, and safety. However, with the recent impact due to the increasing fuel price since 2002, the sale of automobile industry all over the world crippled. This was immediately followed by many questions raised regarding the effect of oil supply shortage on the future of this industry. Many solutions were certainly suggested and many once-considered-infeasible solutions were now given serious second thoughts. Beside the development of electronic car and fuel cell, other proposed approaches include the integration of air conditioning system with electronic devices to cut down energy consumption, the redesign of car frame and body to reduce its total weight, and the modification of car external to improve the car overall aerodynamic characteristics for better cruising conditions, greater stability of navigation, and lower energy consumption. These subjects are also indirectly related to environmental protection and noise pollution. In the process of car design, the aerodynamics must be seriously considered. A car design can only be acceptable if its form drag reduced. Many researchers have made use of CFD techniques [1–4] to perform numerical simulations related to automobile. The current study presents the development process of aerodynamic holography in the vehicle outer- body.Several numerical simulations were performed to analyse the pressure field, velocity vector field, and aerodynamic force prediction related to a passenger car.Then, the stability of the aerodynamic forces caused by the airflow outside the car was identified. After that, the installation of tail plates that leads to lower wind drag is carefully evaluated.Through Fluent [5, 6], this work used k-esteady model to compute the flow properties around the car and its tail plates. As a matter fact, it is very uncommon to use k–e steady model in an iterations-dependent problem. However, it is the goal of this work to demonstrate the feasibility of integrating this very uncommon approach (i.e., the using of k–e steady model) with the computational procedure.Within a relatively short amount of time, this computational process is capable of estimating the aerodynamics of a car at high accuracy.This will provide the automobile research and development teams an alternative approach when performing CAE analysis. In general, the design criteria of tail plate are only limited to considering the aerodynamics aspect due to the tail plates.Car drivers usually install tail plates that successfully reduce the drag and improve traction leading to better manoeuvre.However, the aero-dynamics performance corresponding to the tail plates has deteriorated severely. For this reason, this work has introduced the designers of tail plate a new direction, tool, and idea for tail plate design process. In the following sections, the methodology will be presented in detail.