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This paper concerns with unsteady incompressible flows around rectangular cylinders with side ratio varying from 1 to 10. Phenomenological aspects are discussed and numerical simulations are performed using a SIMPLEC finite volume code. A third-order QUICK scheme is employed for the advective terms in the Navier-Stokes equations, while a second-order fully implicit method is used for the time discretization. For validation purpose, preliminary simulations are carried out at Re = 300. Afterwards, the flow patterns and the wake periodic features are examined at Re = 1,000, 5,000, and 22,000, for which turbulent effects should not be neglected. In some of those cases, large-eddy simulation (LES) is employed, using the classical sub-grid Smagorinsky model. Important physical mechanisms determining vortex shedding frequency are placed in evidence. The present predictions are compared with numerical and experimental results from other works and a good agreement is reached.

The present work investigates the flow and the sound field generated by high subsonic jets in crossflow (JICF). The problem arises when a jet is exhausted perpendicularly into a moving medium. Although being characterized as a very complex flow, the JICF has a well-known fluid dynamics, but a sound field yet to be more explored. Therefore, a hybrid methodology of low computational cost aeroacoustic prediction tool is applied in this work for the complete investigation of this problem. A single jet operating at Mach number 0.75 in a crossflow regime with effective velocity ratios of 4 and 8 is studied herein. The fluid dynamics is solved by the Reynolds Average Navier–Stokes (RANS) equations, and the noise calculations are performed using a statistical method known as the Lighthill Ray-Tracing (LRT) method. The numerical results for the acoustic and flow fields were in reasonable agreement with the experimental data available showing good applicability of this kind of methodology for solving JICF.

The impact of improvement in vehicle aerodynamics mainly reflects in lower fuel consumption and lower carbon dioxide emissions into the atmosphere. The governments of many countries support continuous aerodynamics' improvement programs as a way of mitigating the energy crisis and atmospheric pollution. This work has the main goal to validate experimental and numerical techniques for application in road vehicles. The experimental results were obtained through the analysis of the flow around a standard body with simple geometry called Ahmed Body, using hot wire anemometry from experiments in wind tunnel. It was also proposed a computational validation using a commercial software (Star CCM +) to further analyze the flow and to corroborate the experimental results. Both results were compared and allowed characterizing the flow around the vehicle. The results obtained analyzing the Ahmed Body aimed further application on aerodynamics of heavyduty vehicles, which is an ongoing research being developed at the Experimental Aerodynamics Research Center -CPAERO, in Brazil.