b'Engineer Innovation | Aerospacedistribution and Mach Number contour are shown in Figure 2.The wind tunnel model was 3D printed out of PC-ISO in the Fortus 400 printer. It is printed at one third scale to fit within the printer limits. The wind tunnel test was performed at the NIAR Walter H. Beech wind Figure 1: Cartesian Mesh used in the numerical model for the sUAS. tunnel. It is a subsonic, closed return and atmospheric type with test section of 7x10 in cross sectional dimensions. The model configuration is a sting mount with internal balance. The model with the sting mount is shown in Figure 3.CFD simulations were performed at cruise conditions (Velocity = 50 mph, Reynolds no.750,000). Boundary layers were resolved using the Figure 2: Mach No. contour and surface pressure distribution at Velocity = 50 mph, Angle ofModified Wall Functions approach in Attack= 0. Simcenter FLOEFD. Three methods are available: 1) thin boundary layer The aerodynamic design of sUAS wasSimcenter FLOEFD is based on theapproach, which is based on integral inspired by the following stakeholderFavre-Averaged Navier-Stokes model.boundary layer method, 2) thick requirements:The governing equations areboundary layer, which is based on Van discretized using the finite-volumeDriests velocity profile and 3) hybrid,Tailless, multi-variant configuration;method. The pressure-based solver inwhich combines the thin and thickThe ability to perform search andSimcenter FLOEFD is used in thisboundary layer method. For this study, rescue missions, and drop a payloadstudy. It is based on implicit schemethe thin and hybrid methods were of 5 lbs, cruise velocity of 50 mph;with second order accuracy of spatialinvestigated. The comparison of theForward flight endurance of fivederivatives and first order accuracy ofnumerical results with the hours; and time derivatives. The flow wasexperimental results is shown inMaximum take-off weight of 55 lbscomputed to be fully turbulent andFigures 4 and 5. in order to qualify for the FAA Partthe modified k- two-equation 107 certification category. turbulence model was used. TheExamining Figure 4 it can be seen that Cartesian mesh used in this study isgood agreement exists between the The commercial CFD toolSimcentershown in Figure 1. The pressureSimcenter FLOEFD simulation results FLOEFD software was used to aerodynamically design the sUAS. Simcenter FLOEFD offers many advantages over other CFD codes. Its CAD embedded functionality allows for automatic detection of fluid regions and eliminates the need to modify or clean-up the geometry. Therefore, the lead-time for evaluating multiple design iterations is shorter. The immersed-body Cartesian mesh allows for quickmesh building for any complex geometry. The parametric study of the design for different combinations of airfoils, sweep and incidence angles and dihedral angles was carried out to optimize the aerodynamic performance and to achieve a stableFigure 3: Mach No. contour and surface pressure distribution at Velocity= 50 mph, Angle of configuration.Attack= 0.6'