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"Ailerons."
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Impact of the aileron gap sealing on the aileron effectiveness
Purpose
The purpose of the presented aileron modification analysis is the improvement of the flight handling by eliminating adverse phenomena in the aileron area, such as aileron shaking movements, without the risk of deterioration of flow characteristics during manoeuvres. It was also crucial to reduce aileron forces acting on the control stick.
Design/methodology/approach
Numerical CFD analysis of the aileron system with modifications of sealing in the aileron gap area were performed. The effect of the caulking strip at the upper surface of the aileron gap was determined, as well as caulking at the entrance to the aileron gap on the bottom surface. A solution has also been proposed, consisting of completely closing the aileron gap by using a diaphragm. The three-dimensional flow analysis was carried out, allowing localization of the flow disturbances in the aileron gap at cruising speed. The result of the analysis are the aerodynamic and the hinge moment coefficients determining forces on the control stick, depending on the type of seals.
Findings
It has been shown that the use of subsequent sealing means has a direct impact on the hinge moment value. The results of the CFD analysis showed that the more closed aileron gap is, the higher aileron forces are generated on the control stick. Completely closing the flow in the aileron gap changes the character of the force generated on the control stick.
Practical implications
Through CFD analyses of the aileron gap sealing in the PZL-130 Orlik aircraft, the impact of successive aileron gap sealing on the aileron efficiency was determined. It has been shown that simple change of the aileron gap size by the slat sealing can significantly affect the value of the forces generated on the control stick.
Originality/value
The research using CFD methods allowed to verify the impact of the particular type of aileron gap sealing on the hinge moment value and thus to determine proper sealing configuration for the PZL-130 Orlik aircraft at low computational cost.
Journal Article
Novel Twist Morphing Aileron and Winglet Design for UAS Control and Performance
This study introduces a novel “twist morphing aileron and winglet” design for the Unmanned Aircraft System UAS-S45. Improving rolling efficiency through twist morphing ailerons and reducing induced drag through twist morphing winglets are the two main objectives of this study. A novel wing design is introduced, and a high-fidelity gradient-based aerodynamic shape optimization is performed for twist morphing ailerons and twist morphing winglets, separately, with specified objective functions. The twist morphing aileron is then compared to the conventional hinged aileron configuration in terms of rolling efficiency and other aerodynamic properties, in particular aircraft maneuverability. The results for twist morphing ailerons show that the novel morphing design increases the aileron efficiency by 34% compared to the conventional design and reduces induced drag by 61%. Next, twist morphing winglets are studied regarding the induced drag in cruise and climb flight conditions. The results for twist morphing winglets indicate that the novel design reduces induced drag by 25.7% in cruise flight and up to 16.51% in climb; it also decreases the total drag by up to 7.5% and increases aerodynamic efficiency by up to 9%.
Journal Article
Numerical and experimental transition results evaluation for a morphing wing and aileron system
A new wing-tip concept with morphing upper surface and interchangeable conventional and morphing ailerons was designed, manufactured, bench and wind-tunnel tested. The development of this wing-tip model was performed in the frame of an international CRIAQ project, and the purpose was to demonstrate the wing upper surface and aileron morphing capabilities in improving the wing-tip aerodynamic performances. During numerical optimisation with ‘in-house’ genetic algorithm software, and during wind-tunnel experimental tests, it was demonstrated that the air-flow laminarity over the wing skin was promoted, and the laminar flow was extended with up to 9% of the chord. Drag coefficient reduction of up to 9% was obtained when the morphing aileron was introduced.
Journal Article
Composite Actuation and Adaptive Control for Hypersonic Reentry Vehicles: Mitigating Aerodynamic Ablation via Moving Mass-Aileron Integration
Aerodynamic ablation of external control surfaces and structural complexity in hypersonic reentry vehicles (HRVs) pose significant challenges for maneuverability and system reliability. To address these issues, this study develops a novel bank-to-turn (BTT) control strategy integrating a single internal moving mass with differential ailerons, eliminating reliance on ablation-prone elevators/rudders while enhancing internal space utilization. A coupled 7-DOF dynamics model explicitly quantifies inertial-rolling interactions induced by the moving mass, revealing critical stability boundaries for roll maneuvers. To ensure robustness against aerodynamic uncertainties, aileron failures, and high-frequency mass-induced disturbances, a dynamic inversion controller is augmented with an L1 adaptive layer decoupling estimation from control for improved disturbance rejection. Monte Carlo simulations demonstrate: (1) a 20.6% reduction in roll-tracking error (L2-norm) under combined uncertainties compared to dynamic inversion control, and (2) a 72% suppression of oscillations under aerodynamic variations. Comparative analyses confirm superior transient performance and robustness in worst-case scenarios. This work offers a practical solution for high-maneuverability hypersonic vehicles, with potential applications in reentry vehicle design and multi-actuator system optimization.
Journal Article
Optimizing novel multi-scaled simulation method for deviation analysis of generatively designed aileron bracket using laser powder bed fusion
This research is devoted to forecast the distortion of aileron brackets by means of generative design (GD) and multi-scaled numerical simulation comprising meso- and macro-scaled simulation based on thermomechanical method (TMM) and inherent strain method (ISM), respectively. The multi-scaled simulation began with TMM-based virtual calibration test (VCT) including mesh sensitivity and volume fraction analysis to identify the best meshing voxel size. In finding inherent strain tensors, optimization was implemented using pattern search algorithm referring to the minimum relative error. Further, macro-scaled simulation was implemented to estimate bracket distortion behavior by applying the inherent strain tensors in ISM. For experiment, the conventional aileron bracket shape was first improved by complying the internal rules of GD throughout the desired design space with respect to stress goal and weight reduction based on iterative material distribution. After obtaining the new generatively designed component, linear static analysis was implemented to improve the stress magnitude and surface smoothness level by mesh and material sculpting. Then, the component is manufactured using laser powder bed fusion with manual postprocessing of support structure followed by sand blasting. The finished aileron bracket was then measured using a 3D scanner GOM Atos Q. As conclusion, this novel multi-scaled simulation method based on GD, static stress, and virtual calibration test allows a forecast of an acceptable surface deviation within relative single point and mean errors up to 11% and 5% respectively. By neglecting the tedious and time-consuming procedure of real calibration, a huge time reduction for preparation up to a few days and for computation up to 35% compared to pure TMM can be achieved.
Journal Article
Distributed actuation concepts for a morphing aileron device
The actuation mechanism is a crucial aspect in the design of morphing structures due to the very stringent requirements involving actuation torque, consumed power, and allowable size and weight. In the framework of the CRIAQ MD0-505 project, novel design strategies are investigated to enable morphing of aeronautical structures. This paper deals with the design of a morphing aileron with the main focus on the actuation technology. The morphing aileron consists of segmented 'finger-like' ribs capable of changing the aerofoil camber in order to match target aerodynamic shapes. In this work, lightweight and compact actuation kinematics driven by electromechanical actuators are investigated to actuate the morphing device. An unshafted distributed servo-electromechanical actuation arrangement is employed to realise the transition from the baseline configuration to a set of target aerodynamic shapes by also withstanding the aerodynamics loads. Numerical investigations are detailed to identify the optimal actuation architecture matching as well as the system integratability and structural compactness.
Journal Article
Influence of the air diffusers on human thermal comfort inside vehicles – a review article
The time spent by vehicle occupants in traffic has grown significantly in the last decades. Improving the thermal comfort of the people inside vehicles has gained a lot of importance in the last years both from subjective and objective reasons. The airflow passing through the air diffusers will directly affect the thermal state of the users through its temperature, velocity, and turbulence. A solution to improve the cabin ambiance is to uniformize the airflow inside vehicle through a better mixing between fresh air and ambient air. The automotive industry through its vehicles produced in the last years does not seems to consider this innovative strategy. An idea to improve the air mixing by passive means is using innovative air diffusers which have the capacity to entrain more air than a regular air diffuser. The lobed shaped cross orifice was found to entertain more air than a regular nozzle and derived from this shape more geometries emerged. A good compromise for the air diffuser design in vehicle was found to be the lobed ailerons. The entrainment in the case of the airflow issued from the air diffuser with lobed ailerons it was found to be greater than in the case of the standard air diffuser with straight ailerons.
Journal Article
Stochastic robustness analysis of wing-aileron flutter suppression systems
In this work a stochastic robustness analysis approach is used to compare the performances of two non-linear flutter suppression systems designed for stabilization of a wing-aileron lifting structure. A reduced order modelling approach based on an alternative aeroelastic beam finite element is presented and used for the flutter suppression systems design, which are driven by a simple adaptive controller and a sliding mode controller, respectively. A heuristic algorithm is used to determine the simple adaptive controller invariant parameters at the design point while a simple parametric study is performed to tune the sliding mode controller. The performances of each closed loop system are evaluated taking into account mass, stiffnesses, and aerodynamics uncertainties of the aeroelastic plant also considering the presence of discrete gust disturbances.
Journal Article
Identification of aileron control derivatives based on measured loads in maneuvering flight
When a certain type of aircraft is maneuvered laterally, the aileron and the spoiler will be coupled and deflected to realize the rolling motion of the aircraft. The existing aerodynamic parameter identification methods cannot separately identify the control derivatives of the aileron and the spoiler. Based on the design logic of the aircraft control law and the loading characteristics of the structure during the roll motion, a new method for identifying the aileron control derivative based on the flight measured load is proposed. Firstly, the measurement method of wing aerodynamic load in maneuvering flight is proposed by measuring the structural loads of each load-testing section of the wing in maneuvering flight and combining the structural mass and acceleration distribution outside the section. Secondly, combining the instantaneous rolling moment balance of aircraft lateral control based on the equation and control surface deflection logic, the identification process of aileron control derivatives during roll recovery is deduced, and the identification method of aileron control derivatives based on the measured load of the wing is proposed. Finally, based on the aforementioned method, the identification of aileron control derivatives is carried out, and the influence of different Mach numbers on the derivative of aileron control is analyzed. The results show that the aileron control derivative can be identified based on the flight measured load, and the concentration of the aileron control derivative results is better at the same Mach number. As the Mach number increases, the aileron control effectiveness will decrease. The measured results of flight loads have the potential to be applied to the identification of aerodynamic parameters. 某型飞机横向操纵时副翼和扰流板会耦合偏转实现飞机的滚转运动, 现有气动力参数辨识方法无法单独识别出副翼和扰流板的操纵导数。基于飞机控制律设计逻辑和滚转运动时结构的受载特点, 提出一种基于飞行实测载荷的副翼操纵导数识别方法。通过实测机动飞行中机翼各测载剖面的结构载荷并结合剖面外结构质量与加速度分布, 提出了机动飞行中机翼气动载荷的测量方法; 结合飞机横向操纵瞬时滚转力矩平衡方程和操纵面偏转逻辑, 推导了滚转改出时副翼操纵导数识别过程, 提出了基于机翼实测载荷的副翼操纵导数识别方法; 基于前述方法开展了副翼操纵导数识别, 并分析了不同马赫数对副翼操纵导数的影响。研究表明, 基于飞行实测载荷能够进行副翼操纵导数识别, 而且同一马赫数下副翼操纵导数识别结果集中度较好, 随着马赫数的增加, 副翼操纵效能将会降低。飞行载荷实测结果可用于气动参数辨识工作中。
Journal Article