b'Aerospace | Engineer InnovationFigure 4: Comparison of Lift, Drag and Pitching Moment coefficientsFigure 5: Comparison of Side Force, Yawing and Rolling Moment coefficientsand the wind tunnel results for angles of attack between -10 to 5 using the thin boundary layer approach. This approach also works well for the sideslip angle sweep as can be seen in Figure 5. The hybrid boundary layer approach offers improvement in lift prediction at high angles of attack. Drag prediction at higher angles need further investigation as there was a significant deviation from test. The thermal management of the sUAS internal combustion engine was the second focus of the CFD analysis. A Conjugate Heat Transfer (CHT) analysis was performed to design ducts for improving cooling efficiency of the sUAS internal combustion engine. The CHT analysis is based on heat transfer (Fouriers Law, Newtons Law of Cooling) due to conduction in solids and heat transfer due to convection in fluids (Navier-Stokes equations). The ability to do this in Simcenter FLOEFD provides a powerful tool to the design engineer where this would normally have to be left to the CFD analyst. The comparison of theFigure 6: Comparison of temperature distribution (fluid and solid) for the engine assembly with temperature distribution of the engineand without ducts .assembly with and without the ducts is shown in Figure 6. A reduction of17% in maximum temperature of theNIAR. It allowed multiple design engine assembly is obtained withiteration to be performed on both the ducts and vents incorporated in theaerodynamic design of the drone as assembly.well as optimizing the cooling strategy for the internal combustion engine. Overall Simcenter FLOEFD performedSimcenter FLOEFD has proven to be well and was a valuable tool whenthe go to tool for NIAR and has been designing the demonstrator sUAS forused on numerous projects. n7'