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In the current study, the aerodynamic effects of NACA 2412 cambered & NACA 0012 symmetric airfoils as rear spoilers on a race car were analyzed using the Computational Fluid Dynamics (CFD) technique. Overall nine simulations have been conducted: one with the flow around the simplistic high-speed sports car model with no spoiler and eight for the representation of the flow across the sports car model with spoilers constructed of NACA 2412 and NACA 0012 airfoil having -6°, -3°, +3° and +6° angles of attack, accordingly. The study was conducted using the k-epsilon method as well as for a velocity of 40 m/s. Grid independence study had been conducted and the CFD analysis had been checked by contrasting the results with the famous vehicle aerodynamics experimental study of Ahmed. Among the spoilers studied, this was found that the NACA 0012 with a +6 ° angle of attack ensures a drag reduction of 2.16% and a significant lift reduction of 111.22%. The results of the rear spoiler were described from an aerodynamics viewpoint.

Automotive racing is one of the favorite sports of human being. There have been many developments in past decades by car engineers to improve the performance of the engine and increase the aerodynamic efficiency of the race cars to achieve a better lap time and get a better placement safely. One of the ways to improve the aerodynamic performance of a race car is to use rear spoilers. This study by using ANSYS FLUENT numerically investigated the effect of the spoiler shape and setting angle on the aerodynamic characteristics of a race car and then it was validated by conducting wind tunnel experiment. Lift and drag coefficient of NACA0012, NACA4412, and S1223 are determined in Reynold’s number of 2×105 as an airfoil and as spoiler on ERC model which is a conceptual car model inspired by Porsche 911. It was found that ERC model with spoiler would have better aerodynamic efficiency compared to ERC model without spoiler. Also, S1223 at -6 degrees was identified as the optimized configuration as it generates the highest downforce. Even though the drag coefficient at this setting angle is slightly higher, but in terms of stability and handling IT is at its best. Overall, this study would help car manufacturers, for racing and commercial purposes, to have a better insight into the effect of spoiler configuration on the aerodynamic performance of cars. Hence, the stability, handling, and efficiency of the cars can be further improved by selecting the suitable spoiler configuration.

Aerodynamic characteristics of a vehicle are important elements in its design and construction. A low drag coefficient brings significant fuel savings and increased engine power efficiency. In designing and developing vehicles trough computer simulation process to determine the vehicles aerodynamic characteristics are using dedicated CFD (Computer Fluid Dynamics) software packages. However, the results obtained by this faster and cheaper method, are validated by experiments in wind tunnels tests, which are expensive and were complex testing equipment are used in relatively high costs. Therefore, the emergence and development of new low-cost testing methods to validate CFD simulation results would bring great economic benefits for auto vehicles prototyping process. This paper presents the initial development process of a Formula SAE Student race-car prototype using CFD simulation and also present a measurement system based on low-cost sensors through which CFD simulation results were experimentally validated. CFD software package used for simulation was Solid Works with the FloXpress add-on and experimental measurement system was built using four piezoresistive force sensors FlexiForce type.

Today, high performance race car efficiency is based on a very fine equilibrium between aerodynamic efficiency, engine performance, and chassis behaviour. In particular, from the engine point of view, one way to increase the performance is to increase its volumetric efficiency. The aim of this paper is to present the application of the Large Eddy Simulation (LES) approach for the fluid dynamic analysis of a high performance race car airbox geometry. For a naturally aspired engine, the fluid dynamic optimisation of the airbox geometry means to optimise the energy conversion (from dynamic to static pressure) inside the airbox itself, therefore to increase the flow energy on the engine trumpet sections. The LES approach seems to be the best candidate to investigate such a flow since flow unsteadiness are expected to affect airbox efficiency in terms of pressure recovery. The airbox simulations were performed by using the commercial CFD code Fluent v6.3. The Wall Adaptive Local Eddy-Viscosity (WALE) Sub-Grid Scale (SGS) model was adopted together with a bounded second order central differencing scheme. The LES methodology here adopted was validated by previous works. In order to guarantee realistic fluid dynamic conditions on the airbox inlet section, a part of the car body was considered in the computational domain. Results obtained by LES simulations were analysed in terms of mean and rms evolutions of both pressure and velocity components. This study shows that, today, the LES technique is a very promising and proficient way to obtain detailed information about flow unsteadiness also on industrial cases.