https://repositorio.ufu.br/handle/123456789/19234 2026-10-14T03:07:35Z https://repositorio.ufu.br/handle/123456789/50457 Title: Comparative study of aerodynamic models for aeroelastic flutter prediction and dynamic stall Abstract: The present work reviews and compares the main methods for modeling bidimensional aeroelastic flutter, with particular focus on different aerodynamic formulations and their ability to represent dynamic stall effects. The objective is to provide a comparative view of these methods, serving as an auxiliary set of tools for estimating and predicting experimental results, especially in the context of research aeroelastic tests. Simpler attached-flow formulations, namely quasi-steady and unsteady models, are first investi gated, followed by more advanced semi-empirical dynamic stall models, namely the ONERA and Leishman–Beddoes formulations. All models are numerically implemented in MATLAB and analysed through comparison with a reference experimental case from the literature. By identifying the main characteristics, advantages, and limitations of each approach, it is concluded that, among the attached-flow methods, the unsteady Wagner aerodynamic model provides more accurate predictions than the quasi-steady formulation, since flutter is inherently a high-frequency dynamic phenomenon. Among the semi-empirical models with dynamic stall representation, the Leishman–Beddoes method yields the most satisfactory results, mainly due to the previously validated calibration of its aerodynamic parameters. 2026-03-24T00:00:00Z https://repositorio.ufu.br/handle/123456789/50108 Title: Desenvolvimento de um sistema de controle e guiamento para entrega por paraquedas Abstract: The aim of this work is to develop control and guidance for Precision Aerial Delivery Systems (PADS). To this end, a dynamic model with six degrees of freedom is developed, and based on its linearization, a state-feedback controller is designed using the Linear Quadratic Regulator (LQR) methodology. In addition, a Go-to-Target heuristic is employed to determine the direction that will lead the parachute to the desired target. Thus, the control system performs lateral and longitudinal control of the parachute in order to follow the orientation defined by the heuristic. The influence of the controller parameters on system performance is also analyzed, as well as its behavior under different operating conditions, including the presence and absence of wind. The simulation results demonstrate that the proposed strategy is capable of autonomously guiding the parachute to the vicinity of the desired impact point, offering satisfactory performance combined with simplicity of implementation. However, the approach has limitations related to the heuristic employed, as it is not capable of landing exactly on the target, since it does not constitute a position controller per se. Thus, the development of more sophisticated control strategies is identified as a possibility for future work. 2026-08-06T00:00:00Z https://repositorio.ufu.br/handle/123456789/49039 Title: Artificial neural networks for critical flutter speed prediction in semi-span flat-plate wings with geometric variations 2025-09-30T00:00:00Z https://repositorio.ufu.br/handle/123456789/47947 Title: Estudo do comportamento termomecânico de ferramentais de montagem de estruturas aeronáuticas Abstract: The present work investigates the thermomechanical behavior of assembly tooling for flight critical components, focusing on control surfaces and the effects of thermal expansion on product tolerances. The analysis carried out is extremely useful for assembly processes located in thermally uncontrolled environments. Temperature measurements were performed on the assembly jigs of control surfaces from two aircraft during two hot days, including ambient and ceiling temperatures in the hangar where these tools were located. Structural models were developed to perform finite element analyses (FEA), revealing significant displacements in the vertical and transverse directions, directly impacting hinge tolerances and causing assembly delays in the absence of corrective shims. To generalize the analysis, a thermal model based on the Lumped Capacitance Method (LCM) was created to estimate surface temperatures from environmental conditions. The model showed an average error below 10%, and the subsequent structural analyses confirmed the displacement results with a low error and differences between the built models around 0.06 mm, validating the methodology for future evaluations in assembly processes. 2025-11-06T00:00:00Z