Hatchback versus Sedan – A Review of Drag Issues

International Journal of Mechanical Engineering
© 2017 by SSRG - IJME Journal
Volume 4 Issue 1
Year of Publication : 2017
Authors : Vivek Yakkundi, Shankar Mantha, Vivek Sunnapwar
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How to Cite?

Vivek Yakkundi, Shankar Mantha, Vivek Sunnapwar, "Hatchback versus Sedan – A Review of Drag Issues," SSRG International Journal of Mechanical Engineering, vol. 4,  no. 1, pp. 5-13, 2017. Crossref, https://doi.org/10.14445/23488360/IJME-V4I1P102

Abstract:

Aerodynamic drag or the wind resistance is considered to be of prime concern in vehicle design .The other important issues being the vehicle weight , fuel efficiency & emissions .The twentieth century in particular has witnessed refinement in vehicle design in terms of issues mentioned above. However the focus in this paper is on drag & related issues. It is worth noting that reduction of one count of drag i.e ΔCD = 0.1 translates into an improvement of milage of 2.60 km. As per DOT figures India has approximately 15 million cars plying on the roads as recorded during 2011. Further few hundreds are added every day. Therefore there is enormous scope for improving aerodynamics of cars looking at its growing number, which directly reflects the fuel consumption. It is observed that Hatchbacks or the two box version of cars are becoming popular than contemporary Sedan or the three box version inspite of lower drag value of Sedans, thus creating a conflict of choice amongst customers .The reasons cited are convenience of luggage boot space inside, smaller and compact size due to reduction in wheel base, better power to weight ratio, better manoeuvrability and lesser parking space. In the present paper analysis a midsegment Hatchback and its Sedan version is modelled form its image and CFD analysis is done to predict drag and other aerodynamic characteristics such as lift, flow over the car and analysis of wake / separation in the rear slant. The results of Hatchback and Sedan are compared and it is ascertained that the drag value of Sedan is lower than Hatchback.

Keywords:

Aerodynamics, Turbulence, Computational Fluid Dynamics, Numerical Simulation, Drag

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