The main objective of this paper is an experimental and numerical study of airflow on a propulsive wing also called ventilated wing or FANWING, which is a drone operating at low speed. To optimize the aerodynamic shape of the Fanwing, two different configurations of NACA4415 rectangular wing profile were realized. The first one is a wing where the Cross-Flow Fan is fitted directly to the leading edge with a classic niche. For the second one, we truncated the extension of the niche to create a profile without nose. Two flow velocities with constant fan rotation were used and observed in the range of −16°< α < +30°. A lift coefficient generated by the profiles increases and the drag coefficient decreases, while the distribution of the pressure coefficient on the upper surface increases abruptly because of the flow recirculation. The experiment was performed in a subsonic wind tunnel TE44 and numerical simulations in software Fluent 6.3.2.6. Both approaches are in good agreement. The visualization showed that the recirculation phenomenon occurs right after the discharge of the cross-flow fan. It reveals that the jet coming out of the fan causes a strong wake behind the profile and suppresses the boundary layer separation.

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The present investigation set out to assess the influence of the surface roughness on the flow and thermal mean quantities, around the heated corrugated cylinder in the laminar steady flow. The current investigation has been devoted to a numerical analysis of a two-dimensional steady flow and forced convection heat transfer characteristics over a heated longitudinal sinusoidal shape grooved cylinder, immersed in an unconfined Newtonian fluid. The number of the grooved cavities was chosen to be 10, 20 and 30 grooves, equally distributed around the cylinder circumference with wavelength and wave amplitude of 1/50 and 1, respectively. Moreover, the thermal boundary condition effect has been analyzed by imposing a uniform heat flux and constant temperature on the cylinder periphery as a thermal boundary condition, over a Reynolds number range of ([Formula: see text]) and a fixed Prandtl number of 0.715. The numerical procedure is based on the finite volume method. The findings indicate that with increasing groove number, the total drag coefficient of the grooved cylinder reduces markedly compared to the smooth one. This trend is more pronounced as the Reynolds number increases. The effect of the groove number on the pressure coefficients is limited, where the profiles of the grooved cylinder coincide with that of the smooth one over the Reynolds number range. When the Reynolds number varies from 0.1 to 40, the average Nusselt number enhances noticeably by about 86% for the smooth and grooved cylinders. Moreover, the groove number affects significantly the average Nusselt number, where the increased groove number results in a gradual reduction in the average Nusselt number. This attenuation is more pronounced as the Reynolds number increases. To predict the average Nusselt number, a correlation has been proposed.