Take-Home Messages Earth observation microwave radiometer payload based on an L-band deployable offset reflector for CubeSat.  Optimal offset reflector configuration analyzed has a circular shape and regular mesh.  Regular meshes perform better than irregular ones, but the required supporting structure is larger.

Abstract. The objective of this paper is to study the effect of an unsteady moving heat source on the aerodynamic performance of an NACA 0012 airfoil section, with particular focus on the lift and drag coefficients. The compressible Navier-Stokes equations are solved using a finite volume method as well as Spalart-Allmaras Model for turbulence simulation. The heat source periodically moves over the lower surface of the airfoil in the downstream direction. The numerical results show how the drag and lift coefficient strongly depend upon the velocity of the source. For a constant source power, a progressive improvement in the mean values of lift and drag coefficients is observed as velocity increases.Keywords: aerodynamic performance, heat source, lift coefficient, drag coefficient, computational fluid dynamics. IntroductionOptimizing aerodynamic performance and increasing the reliability of flying machines has led scientists to find new methods that simultaneously provide increase in the lift and reduce drag. One of those approaches has been using procedures based on heat transfer effects. Over the last decades, several numerical and analytical methods to study heat effects have been developed. Generally, the effect is studied by imposing steady temperature differences between the airfoil surface and the freestream. For example, Norton et al. (1973) [1] studied the case of NACA 0012 heated at different ratios and considering both laminar and turbulent flows over the surface. Their results showed a destabilization of the boundary layer, earlier transition and separation for temperature ratio bigger than unity. The paper showed a reduction in the value of Cl max and an increase in drag as the airfoil was heated.