Numerical Investigation of Aerodynamic Braking for a Ground Vehicle

• Published in: Journal of the Institution of Engineers (India) Series C Vol. 99; no. 3; pp. 329 - 337
• Main Author: Devanuri, Jaya Krishna
• Format: Journal Article
• Language: English
• Published: New Delhi Springer India 01.06.2018; Springer Nature B.V
• Subjects: Aerodynamic characteristics; Aerodynamics; Aerospace Technology and Astronautics; Automotive bodies; Brakes; Braking; Braking systems; Computational fluid dynamics; Drag coefficients; Engineering; Inclination; Industrial and Production Engineering; K-epsilon turbulence model; Maintenance management; Mathematical models; Mechanical Engineering; Numerical analysis; Original Contribution; Parameters; Taguchi methods; Three dimensional bodies; Aerodynamic brake; Ahmed body; Computational fluid dynamics; Ground vehicle; Aerodynamics; Optimization; Taguchi method
• ISSN: 2250-0545; 2250-0553
• DOI: 10.1007/s40032-017-0385-7

The purpose of this article is to observe the effect of an air brake on the aerodynamics of a ground vehicle and also to study the influence of change in the parameters like the velocity of the vehicle, the angle of inclination, height, and position of the air brake on the aerodynamics of the vehicle body. The test subject used is an Ahmed body which is a generic 3D car body as it retains all the aerodynamic characteristics of a ground vehicle. Numerical investigation has been carried out by RNG k-ε turbulence model. Results are presented in terms of streamlines and drag coefficient to understand the influence of pertinent parameters on flow physics. It is found that with the use of an air brake, though the drag coefficient remains more or less constant with velocity, it increases with the increase in height and angle of inclination of the air brake. But the effect of position of air brake on the coefficient of drag is surprising since for certain heights of the air brake the drag coefficient is maximum at the foremost point and as the air brake moves towards the rear it is first observed to decrease and then increase. It is also observed that with the increase in height of the air brake the drag coefficient monotonically decreases as the position of the air brake is moved towards the rear. Taguchi method has been employed with L16 orthogonal array to obtain the optimal configuration for the air brake. For each of the selected parameters, four different levels have been chosen to obtain the maximum drag coefficient value. The study could provide an invaluable database for the optimal design of an airbrake for a ground vehicle.