Aerodynamic optimization using add-on devices: comparison between CFD and wind tunnel experimental test
2022-01-1082
3/29/2022
- Content
- JUNO is an urban concept vehicle (developed at the Politecnico of Torino), equipped by an ethanol combustion engine, designed to obtain low consumptions and reduced environmental impact. For this goals the main requirements that were considered during the designing process are mass reduction and aerodynamic optimization, at first on the shape of the car body and then, thanks to external appendix. JUNO’s aerodynamic development follow a defined workflow: geometry definition and modelling, CFD simulations and analysis, and finally geometry changes and CFD new verification. In this paper are compared the results of the CFD simulations (using STARCCM+, RANS k-ε) with a corresponding 1/1 scale wind tunnel (of FCA group in Orbassano- Torino), tests made using the real vehicle. Particularly, the results in term of: total drag coefficient (Cx), total lift coefficient (Cz), the total pressure scene in the side and rears analyzing twenty different aerodynamics configurations made up of different combination of some aerodynamics appendages. From the analysis of the results is emerged that CFD simulations using RANS methods are able to guess the trend of total drag coefficient and also its absolute value, deviating by less than 10% in all the cases in which the high error value for all the spoiler included configurations. As regard the trend and the absolute value for lift coefficient, are much larger deviation than Cx. For total pressure scene, there is a high similarity between the two ways of testing, especially on the side and on the central rear zone. The CFD results simulations, RANS k-ε are good to develop and test symmetrical wide body in fact, they are in good agreement with wind tunnel results but, with particular attention to geometry, that suddenly change the way of air-flow.
- Citation
- Carello, M., and Verratti, M., "Aerodynamic optimization using add-on devices: comparison between CFD and wind tunnel experimental test," SAE Technical Paper 2022-01-1082, 2022, .