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.

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omputational aerodynamics analyses of a NACA air intake assembled in a canard type aircraft is performed in this work. Semi-empirical calculation through the ESDU (Engineering Science Database Unit) preceded the CFD simulations to define the geometric size of the air intake as well to check its efficiency and drag estimation. The NACA air inlet was considered one of the best options available for implementing in a canard type aircraft since it reduces aerodynamic drag by avoiding protuberances in the fuselage. Numerical studies were performed with the air intake mounted in the aircraft's fuselage at operational flight conditions. These simulations were performed using Reynolds-averaged Navier-Stokes (RANS) and turbulence modeling by using the k-ω SST (Shear-Stress Transport). Data analyses were based on the air inlet efficiency, drag estimation and mainly flow characterization. The numerical results helped to characterize the flow in a canard type aircraft showing that the NACA air intake yielded satisfactory performance with low drag. The approach applied in this work was a partnership with the Brazilian Aircraft Factory (FABE) and Federal University of Uberlândia (UFU) to improve the design of a canard type aircraft. The CFD results have been corroborated by an empirical approach and with some experimental tests performed by the company, pointing towards the reliability of a very efficient design tool for application in industry.

Low and high speed subsonic jets have been studied in the last 50 years mainly due to their many applications in industry, such as the discharge of turbojets and turbofan engines. The purpose of this work is to investigate the aerodynamics and the acoustical noise generated by a single stream jet flow operating at low Mach number 0.25 and Reynolds number of 2.1 × 10 5 . The main focus is the flow and acoustical characterization of this low speed jet by applying different experimental techniques for evaluating the velocity field by using measurements with a Pitot tube, hot-wire anemometry, and farfield noise acquisition by free field microphones. In order to verify the validity of aeroacoustic predictions for such a low speed jet, a Computational Fluid Dynamics by means of RANS simulations via k-ω SST model have been employed coupled with a statistically low-cost Lighthill-Ray-Tracing method in order to numerically predict the acoustic noise spectrum. The sound pressure level as a function of frequency is contructed from the experiments and compared with the noise calculations from the acoustic modeling. The numerical results for the acoustics and flow fields were well compared with the experimental data, thus showing that this low-cost flow-acoustic methodology can be used to predict the acoustic noise of subsonic jet flows, even at low speeds. R Observer's radius [m] NOMENCLATURE

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