The comparison of vortex lattice and panel methods in low Reynolds number aerodynamic analysis

The conceptual design phase is the most crucial phase of the aircraft design process as it determines the aircraft's overall geometry through decisions made during this phase. The shape of the airplane is determined by performing aerodynamic analyses that evaluate the performance requirements using static aerodynamic coefficients during the decision stages. In order to reach the optimal result during this phase, it is important to utilize design and analysis tools that are both time-efficient and cost-effective as the aircraft geometry changes iteratively and continuously. The conceptual design process has seen the frequent use of panel and vortex lattice methods, which provide fast and simple solutions and are low-cost, in the early stages of aircraft design processes in recent years. Panel and Vortex Lattice Methods; based on potential flow theory, describe the effects of flow on surfaces by dividing the surface of objects into small panels under incompressible, linear, inviscid, and irrotational flow conditions. By employing software, it is possible to calculate the lift, drag, and moment coefficients of a wing at low and medium angle of attack using the mathematical models of Panel and Vortex Lattice Methods. In this thesis, it is aimed to estimate and compare the coefficients required for the aerodynamic modeling of an aircraft by using low-order aerodynamic analysis methods, such as Panel, Vortex Lattice and semi-empirical methods, in low Reynolds number aerodynamic analysis. In the initial phase of the study, the success of the methods was assessed and compared the methods, based on wind tunnel test results of NACA 4415 wing geometries with different aspect ratios, which were modeled and analyzed aerodynamically in XFLR5, OpenVSP, and Digital DATCOM software. In the second phase, the Trainer 60 aircraft was modeled and analyzed aerodynamically with the same software. The methods and software were compared by interpreting the results of the analyses based on static aerodynamic coefficients.