Showing papers on "Fuselage published in 2017"
29 Jun 2017
TL;DR: The first appearance of the new model FCX-001 took place at Heli Expo 2017 in Dallas, Texas, where the new concept of the aircraft was presented in this highly stylized form.
Abstract: Bell Helicopter is always preparing beautiful surprises for us, so this year has not been outdone and has revealed its vision of its future aircraft model FCX-001, a true vertical elevator, ment to can climb to high altitudes in a record time, with an enviable dynamics and maneuverability. The first appearance of the new model FCX-001 took place at Heli Expo 2017 in Dallas, Texas, where the new concept of the aircraft was presented in this highly stylized form. The aircraft appeared in the Bell stand, both in the form of a large-scale layout and in the virtual reality by using immersive helmets, the two-engine ship incorporating some of the new technologies currently under development at Bell and it is very likely to mature in the near future. At first glance, you are astonished at a cockpit that is totally devoid of physical controls, as if the ship were to run alone, fully automated. Notable elements in the design of the FCX-001 include a fan-driven anti-torque system, hybrid propulsion system, main rotor blade tips, extensive use of fuselage glass, winged doors and the use of augmented reality in the cockpit to control the aircraft. On the very roomy cabin ceiling of the aircraft, configured for only eight passengers in the Heli-Expo model, but able to adapt up to 12 passengers, Bell introduced a "drop-down" control module to allow personalization maximum and increased passenger comfort. The concept is provided with various modules that provide passengers with the ability to adjust their own things, such as cabin light intensity, interior temperature, or infotainment system. When looking closely at the new FCX-001 concept, starting with the back of the aircraft, it does not have a tail rotor (which is essential and notable for Bell's new model). In order to achieve the anti-torque instead, a new multi-rotor system is needed in the hood. It gives the aircraft the ability to push in both directions and also has vector control of the traction, also allowing it to give up a horizontal stabilizer. The anti-torque system is acted by an electric motor as part of a hybridized propulsion system. At the top of the aircraft, the main rotor blades (morphing) have an attractive design. At the same time, technology aims to allow the tip of each blade to move between the different flight regimes, just like a "swing wing" on an airplane to maximize efficiency and performance and reduce noise. The actual airframe of the aircraft is also very different from what Bell used in the past. In terms of ladder, the FCX-001 is slightly larger than a Bell 412 both in terms of its length and width, its new lines and its use of massive glass exhibiting some production challenges that rely on the new composite structures, today so widely used in the aviation and aerospace industries.
84 citations
TL;DR: In this paper, an optimized and comprehensive method is used to design and manufacture a fixed wing micro air vehicle (MAV) with Zimmerman planform, and the results show that an optimum aspect ratio that maximizes the performance of the Zimmerman MAV for a well defined cruise speed is determined.
Abstract: An optimized and comprehensive method is used to design and manufacture a fixed wing micro air vehicle (MAV) with Zimmerman planform. The design process includes four stages which are the specification of the flight mission, determination of the best aspect ratio, identification of the optimum wing loading and thrust loading values, and estimation of the weight of the structural components of the MAV. To do this, various statistical and analytical methods are utilized. Based on an aerodynamic analysis, the results show that an optimum aspect ratio that maximizes the performance of the Zimmerman MAV for a well-defined cruise speed is determined. Considering six possible flights, a constraint analysis is performed and an optimum wing loading value is determined. It is shown that the computational method is beneficial to determine the exact masses for the structural components including the wing, fuselage, and vertical tail. Using the 3D panel method, the determination of the shape of the reflexed airfoil for the MAV is successfully done by minimizing the drag force and the angle of attack to use less powerful motor and avoid any stall effect, respectively. A stability analysis is then performed to check the safe flight of the designed vehicle. During test flight, the results show that the designed Zimmerman MAV satisfies the pre-defined specification. The final characteristics of the manufactured MAV are: wingspan of 44 cm, weight of 450 g, aspect ratio of 1.51, cruise speed of 20 m/s, and flight endurance of 20 min.
76 citations
TL;DR: From the results of RANS simulations on a modular model of a representative regional turboprop airplane layout, the authors have developed a modern method to evaluate the vertical tail and fuselage contributions to aircraft directional stability.
55 citations
TL;DR: In this article, simultaneous longitudinal and lateral flight control systems design for both passive and active morphing tactical unmanned aerial vehicles (TUAVs) is first time applied for autonomous flight performance maximization in the literature.
Abstract: In this article, simultaneous longitudinal and lateral flight control systems design for both passive and active morphing tactical unmanned aerial vehicles (TUAVs) is first time applied for autonomous flight performance maximization in the literature. For this purpose longitudinal and lateral dynamics modelling of TUAVs produced in Erciyes University, Faculty of Aeronautics and Astronautics, Model Aircraft Laboratory are considered in order to obtain simulation environments. Our produced TUAV is called as ZANKA-III which has weight of 50 kg, range of around 3000 km, endurance of around 28 hour, and ceiling altitude of around 12500 m. Von-Karman turbulence modelling is used in order to model atmospheric turbulence during flight in both longitudinal and lateral simulation environments. A stochastic optimization method called as simultaneous perturbation stochastic approximation (i.e. SPSA) is also first time applied in order to obtain optimum dimensions of morphing parameters (i.e. extension ratios of wingspan and tailspan, assembly positions of wing and tailplane to fuselage) and optimum magnitudes of longitudinal and lateral controllers’ gains (i.e. P, I and D gains) while minimizing cost index capturing terms about both longitudinal and lateral autonomous flight performances and there exists lower and upper constraints on all optimization variables in the literature.DOI: http://dx.doi.org/10.5755/j01.eie.23.5.19238
42 citations
TL;DR: In this article, high-fidelity aerodynamic shape optimization based on the Reynolds-averaged Navier-Stokes equations is used to optimize the aerodynamic performance of a conventional tube-and-wing design, a hybrid.
Abstract: High-fidelity aerodynamic shape optimization based on the Reynolds-averaged Navier–Stokes equations is used to optimize the aerodynamic performance of a conventional tube-and-wing design, a hybrid
41 citations
TL;DR: In this article, the authors presented aerodynamic calculations of the model-scale ERICA tiltrotor with high-fidelity computational fluid dynamics (CFD) to assess the capability of the present CFD method in predicting airloads on the tilt-rotor at different flight configurations.
41 citations
TL;DR: In this paper, an improved radial braiding model was developed and applied to a complex fuselage frame technological demonstrator for overbraiding with carbon fiber yarns, which resulted in a greater difference between the web and the flange faces.
Abstract: Braided structural composites have the potential to replace aerospace primary structure traditionally manufactured with preimpregnated fabrics and cured in autoclave. An improved braiding model was developed and applied to a complex fuselage frame technological demonstrator. Numerical case studies were performed in order to assess their effectiveness and to determine the best braiding parameters. A radial braiding machine was coupled to an industrial robot. The fuselage frame demonstrator mandrel was overbraided with carbon fiber yarns. Measured braid angles showed a greater difference than what was expected between the web and the flange faces. Yarn friction and interlacing forces caused the yarns to curve near the edges of the face, therefore causing the measured braid angles to vary along the face width. Moreover, discrepancies in the model’s outputs prevented the braid fell front to conform around the severe cross-section variations as well as causing yarn slip over the corners.
39 citations
TL;DR: Results show that constraint errors of posture adjustment obtained by the multi-objective optimization model are not out of tolerance for design constraint errors and satisfy the requirement of aircraft fuselage joining assembly.
39 citations
Patent•
14 Mar 2017
TL;DR: In this article, a rotatable wing is attached to the wing support and configured to rotate between a vertical flight configuration in which the inboard portion is positioned on an opposing side of the wing Support relative to the outboard portion, and a horizontal flight configuration different from the vertical flight configurations.
Abstract: A tailsitter aircraft includes one or more rotatable wings. The tailsitter aircraft optionally includes a fuselage from which wing supports extend. Each rotatable wing optionally includes a rotatable wing section having an inboard portion proximate to the fuselage, and an outboard portion distal from the fuselage. The rotatable wing section may be rotatably attached to the wing support and configured to rotate between a vertical flight configuration in which the inboard portion is positioned on an opposing side of the wing support relative to the outboard portion, and a horizontal flight configuration different from the vertical flight configuration. The wings may be rotated during flight to transition between horizontal and vertical flight configurations, and they may be rotated about multiple axes.
36 citations
TL;DR: In this article, an extended integrated layout and topology optimization method was proposed to deal with the multi-frame and multi-component fuselage structure systems design considering an aircraft or aerospace fuselage system including main structure, numbers of frames and featured components located on the frames.
Abstract: The purpose of this paper is to present an extended integrated layout and topology optimization method dealing with the multi-frame and multi-component fuselage structure systems design. Considering an aircraft or aerospace fuselage system including main structure, numbers of frames and featured components located on the frames, a simultaneous optimization procedure is proposed here including geometrical design variables of components and frames as well as topological design variables of main structure and frame structures. The multi-point constraints (MPC) scheme is used to simulate the rivets or bolts connecting the components, frames and structures. The finite circle method (FCM) is implemented to avoid the overlaps among different components and frames. Furthermore, to deal with the difficulties of large numbers of non-overlapping constraints, a penalty method is used here to compose the global strain energy and non-overlapping constraints into a single objective function. To guarantee the fuselage system's balance, the constraint on the system centroid is also introduced into the optimization. Different numerical examples are tested and the optimized solutions have demonstrated the validity and effectiveness of the proposed formulation.
35 citations
Patent•
22 Feb 2017
TL;DR: In this paper, the authors proposed a UAV consisting of a fuselage, wings and a tail, where transverse threaded holes and longitudinal threaded holes are formed in the wing connecting positions of the fuselage and the tail connecting position of the UAV.
Abstract: The invention belongs to the technical field of air vehicles and particularly relates to an unmanned aerial vehicle. The unmanned aerial vehicle comprises a fuselage, wings and a tail, wherein transverse threaded holes and longitudinal threaded holes are formed in wing connecting positions of the fuselage, transverse threaded holes and longitudinal threaded holes are formed in a tail connecting position of the fuselage, transverse threaded holes and longitudinal threaded holes are formed in the wings, transverse threaded holes and longitudinal threaded holes are formed in the tail, the transverse threaded holes in the wing connecting positions of the fuselage are connected with the transverse threaded holes in the wings through bolts, the longitudinal threaded holes in the wing connecting positions of the fuselage are connected with the longitudinal threaded holes in the wings through bolts, the transverse threaded holes in the tail connecting position of the fuselage are connected with the transverse threaded holes in the tail through bolts, and the longitudinal threaded holes in the tail connecting position of the fuselage are connected with the longitudinal threaded holes in the tail through bolts. According to the unmanned aerial vehicle, not only is the assembly and disassembly time of the unmanned aerial vehicle saved, but also the labor intensity of workers is reduced.
Patent•
11 Jan 2017
TL;DR: In this article, a hybrid propulsion aircraft (100) is described having a distributed electric propulsion system, which includes a turbo shaft engine (112) that drives one or more generators (116) through a gearbox.
Abstract: A hybrid propulsion aircraft (100) is described having a distributed electric propulsion system. The distributed electric propulsion system includes a turbo shaft engine (112) that drives one or more generators (116) through a gearbox (132). The generator (116) provides AC power to a plurality of ducted fans (108, 110), each being driven by an electric motor (506). The ducted fans (108, 110) may be integrated with the hybrid propulsion aircraft's wings (104, 106). The wings (104, 106) can be pivotally attached to the fuselage (102), thereby allowing for vertical take-off and landing. The design of the hybrid propulsion aircraft (100) mitigates undesirable transient behavior traditionally encountered during a transition from vertical flight to horizontal flight. Moreover, the hybrid propulsion aircraft (100) offers a fast, constant-altitude transition, without requiring a climb or dive to transition. It also offers increased efficiency in both hover and forward flight versus other VTOL aircraft and a higher forward max speed than traditional rotorcraft.
TL;DR: In this paper, the authors performed detailed analysis of the rotor downwash effects on ice that accretes on a helicopter fuselage and to determine the variation with respect to the forward flight speed.
Abstract: To accurately predict the ice shape on the fuselage under rotor-wake effects, discrete modeling of individual tip vortices is essential to determine the local aerodynamic interactions between the vortex and the fuselage. To this end, the actuator surface model is developed and applied to the present study. Then, water-droplet-trajectory prediction, thermal analysis, and ice growth module are seamlessly integrated. This study aims to perform detailed analysis of the rotor downwash effects on ice that accretes on a helicopter fuselage and to determine the variation with respect to the forward flight speed. As a result of comprehensive numerical computations, the following conclusions are reached. First, the rotor inflow transforms the droplet trajectories, the location of ice accretion and the amount of ice are changed. Actually, 16.5% less ice is accumulated on the overall fuselage in the rotor–fuselage interaction case compared to the isolated fuselage case. Second, a clear-cut distinction of the icing lo...
TL;DR: In this article, a CAD-based shape parametrisation method was proposed for aerodynamic shape optimization of fully-featured aircraft characterised by complex intersecting surfaces using an adjoint solver based on Reynolds-averaged Navier-Stokes equations.
TL;DR: In this article, the impact resistance of UHP-SFRC panels subjected to the aircraft engine was investigated by using a series of reduce-scaled engine model perforation test, in which the residual velocities of the engine missiles as well as the damage of both engine missile and target slab were derived and assessed.
Patent•
2 Jun 2017TL;DR: In this article, the authors present a system for an aircraft having a fuselage (110); a wing (120) extending from both sides of the fuselage; a first pair of motors (132b, 133b) disposed at a first end of the wing; and a second pair of engines (142b, 143b), disposed at the second end of a wing; where each motor is angled (381, 382, 391, 392) to provide a component of thrust by a propeller (134, 135, 144, 145) attached thereto that for a
Abstract: Systems, devices, and methods for an aircraft having a fuselage (110); a wing (120) extending from both sides of the fuselage; a first pair of motors (132b, 133b) disposed at a first end of the wing; and a second pair of motors (142b, 143b) disposed at a second end of the wing; where each motor is angled (381, 382, 391, 392) to provide a component of thrust by a propeller (134, 135, 144, 145) attached thereto that for a desired aircraft movement applies a resulting torque additive to the resulting torque created by rotating the propellers.
9 Jan 2017
TL;DR: In this paper, preliminary results of an in-flight thrust measurement method are presented in order to determine the drag force generated by the aircraft, which is obtained by sensor fusion of Gaussian signals.
Abstract: Preliminary results of an in-flight thrust measurement method are presented in order to determine the drag force. Flight experiments are conducted by an off-the-shelf aircraft which has been equipped with an autopilot system and additional sensors measuring the electric motor rotation speed, battery voltage, drawn current, and direct thrust of the motor. Several level cruise flights have been performed in order to measure the thrust, thus the drag force generated by the aircraft. The propulsion system used on the aircraft is first characterized in the wind-tunnel. The direct thrust measurement system which is on-board the aircraft presents a lot of noise coming from vibrations, characteristics of the sensor itself, and also the fuselage wake and propeller interaction. Hence a better estimation of the in-flight thrust and the resultant drag is obtained by sensor fusion of Gaussian signals.
TL;DR: In this paper, a formulation of the dynamic equilibrium equation employing a decoupled approach for the joint mechanical properties of an assembly is presented, and an optimization process based on this formulation that involves the joint properties as design variables has been developed in order to identify the joint parameters that improve the adjustment between numerical and experimental FRF in the case of harmonic excitations.
Patent•
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TL;DR: In this paper, the X-tiltwing has oppositely disposed V-wing members each having first and second wing sections, and a flight control system is associated with the distributed propulsion system to independently control each of the propulsion assemblies.
Abstract: An aircraft having a vertical takeoff and landing flight mode and a forward flight mode. The aircraft includes a fuselage and an X-tiltwing that is rotatable relative to the fuselage between a vertical lift orientation and a forward thrust orientation. The X-tiltwing has oppositely disposed V-wing members each having first and second wing sections. In the vertical lift orientation, the first and second wing sections of each V-wing member are generally in the same horizontal plane. In the forward thrust orientation, the first and second wing sections of each V-wing member are generally in the same vertical plane. A distributed propulsion system is attached to the X-tiltwing such that a plurality of propulsion assemblies is attached to each wing section. A flight control system is operably associated with the distributed propulsion system to independently control each of the propulsion assemblies.
5 Jun 2017
TL;DR: In this paper, the authors extended the adjoint-based design capability in FUN3D to allow efficient gradient-based optimization and design of concepts with highly integrated aero-propulsive systems.
Abstract: The adjoint-based design capability in FUN3D is extended to allow efficient gradient- based optimization and design of concepts with highly integrated aero-propulsive systems. A circumferential distortion calculation, along with the derivatives needed to perform adjoint-based design, have been implemented in FUN3D. This newly implemented distortion calculation can be used not only for design but also to drive the existing mesh adaptation process and reduce the error associated with the fan distortion calculation. The design capability is demonstrated by the shape optimization of an in-house aircraft concept equipped with an aft fuselage propulsor. The optimization objective is the minimization of flow distortion at the aerodynamic interface plane of this aft fuselage propulsor.
Patent•
15 Mar 2017
TL;DR: In this article, the utility model discloses a many ducts VTOL unmanned aerial vehicle, including the fuselage, the undercarriage, the wing including central wing and outer section wing, adopts the quick assembly disassembly structural connection.
Abstract: The utility model discloses a many ducts VTOL unmanned aerial vehicle, this unmanned aerial vehicle includes: the fuselage, the undercarriage, the wing including central wing and outer section wing, adopts the quick assembly disassembly structural connection, lift ducted fan, its by -pass air duct and outer section wing adopt integrated into one piece's structure, impel the screw, be located the afterbody of fuselage, vertical tail and tailplane constitute the twin -finned layout, trim ducted fan. At vertical take -off cruise at a high speed vertical landing in -process, trim ducted fan are used for providing the required new line of vertical every single move of VTOL stage and bow moment, provide the yawing moment in VTOL stage through deflection, lift when lift ducted fan is used for providing the VTOL, impel the screw to be used for providing the flat required thrust that flies. The utility model discloses an unmanned aerial vehicle can be applicable to scenes such as electric power inspection, environment monitoring in the descending of taking off of narrow and small space, has quick assembly disassembly, portable, advantages such as the voyage is big, flight performance is good.
Patent•
17 May 2017
TL;DR: In this paper, an efficient vertical takeoff and landing aircraft with a fixed-wing undercarriage is presented, where a power unit is installed on each of the wing and the horizontal tail, a part of the lift at the vertical takeoff stage is provided by the wing propeller power unit, and the tail propeller powered unit is responsible for the aircraft pitch balance adjustment; the power device installed on the wing is closed in the flat flight state, and tail propulsion unit provides forward thrust in order to improve the aircraft efficiency in a cruising state.
Abstract: The invention relates to an efficient vertical takeoff and landing aircraft, and discloses an efficient vertical takeoff and landing fixed-wing unmanned aerial vehicle, which comprises a fuselage, a wing, a horizontal tail, a vertical tail, a control surface, a power unit, a tilting mechanism and an undercarriage. The tilting mechanism controls the tilting angle of the wing and the horizontal tail to realize the mutual conversion of a vertical takeoff and landing state and a flat flight state of the aircraft. A propeller power unit is arranged on each of the wing and the horizontal tail, a part of lift at the vertical takeoff and landing stage is provided by the wing propeller power unit, and the tail propeller power unit is responsible for the aircraft pitch balance adjustment; the power device installed on the wing is closed in the flat flight state, and the tail propeller power unit provides forward thrust in order to improve the efficiency of the aircraft in a cruising state. Compared with the existing vertical takeoff and landing fixed-wing unmanned aerial vehicle design scheme, the flight aerodynamic efficiency of the aircraft in the fixed-wing flat flight state is taken into account while the layout is simplified, and reliability and practicability are relatively high.
Patent•
15 Aug 2017
TL;DR: In this article, a tilt-rotor unmanned aerial vehicle is characterized in that the power system comprises wing power devices arranged on the wings, tail planes, oil tanks and oil transferring pipelines, and the power devices and the oil tanks are distributed symmetrically on the two sides of the vertical symmetrical face of the fuselage.
Abstract: A tilt-rotor unmanned aerial vehicle comprises a fuselage, tilted wings, tilted tail planes, a vertical empennage, a power system and a landing gear. The tilt-rotor unmanned aerial vehicle is characterized in that the power system comprises wing power devices arranged on the wings, tail plane power devices arranged on the tail planes, oil tanks and oil transferring pipelines, and the power devices and the oil tanks are distributed symmetrically on the two sides of the vertical symmetrical face of the fuselage. The wing power devices and/or the empennage power devices comprise pinch control mechanisms, and the pinch control mechanisms can adjust angles between paddles of a propeller and the axis of the paddles through mechanical transmission. The wings and the tail planes can tilt at large angles through tilting mechanisms, and free conversion between a multi-rotor mode and a fixed wing mode can be achieved under control of a control system.
TL;DR: In this paper, an automatic precise shaft-hole assembly method for aircraft assembly using 5 degrees of freedom spatial mechanism, compliance technology and servo feeding system has been developed, and the model of compliant assembly for shafthole mating is constructed, and force condition analysis of the compliant assembly is performed.
Abstract: Purpose
The purpose of this paper is to design a new method to realize automatic assembly of aircraft components with large shafts such as canard and vertical tail. The assembly structure of component with large shaft and fuselage is a mating assembly structure, and it is a challenge to satisfy the precision and assembly requirement.
Design/methodology/approach
According to the assembly structure features and process requirements of an aircraft component with large shaft, the operating principle of precise assembly system for shaft-hole mating is analyzed in this paper. The model of compliant assembly for shaft-hole mating is constructed, and force condition analysis of the compliant assembly is performed. An automatic precise shaft-hole assembly method for aircraft assembly using 5 degrees of freedom spatial mechanism, compliance technology and servo feeding system is put forward based on the analysis. A 5 degrees of freedom passive compliant experimental equipment has been developed.
Findings
Application test results of the 5 degrees of freedom passive compliant experimental equipment show that the simulated canard can be mated automatically and accurately through this method with high efficiency and high quality as long as the tip of shaft enters into the range of hole’s chamfer.
Practical implications
This method has been used in an aircraft assembly project. The practical results show that the aircraft components with large shafts can be mated automatically and accurately through this method with high efficiency and high quality.
Originality/value
This paper presents a new method and designs a new assembly system to realize the assembly of the aircraft components with large shafts. The research will promote the automation of fuselage assembly.
Patent•
9 Mar 2017
TL;DR: In this article, an actuation and feedback control system is used to control the rotational speed of each wing and the tilt angles of the rudder on the basis of given flight inputs such as aircraft direction and speed.
Abstract: The present invention, in the field of aviation, is a Vertical Take-Off and Landing (VTOL) vehicle comprising fuselage, verticale tail, four tilting wings, electric generator which uses liquid fuel, rechargeable electric energy storage devices, sensors comprising air flow sensors and an actuation and feedback control system. The four tilting wings may rotate, independently one from the other and in a controlled way, around two axes parallel to the pitch axis, one of these axis is in front of the center of gravity of the vehicle and the other behind it. All the four wings provide positive lift during forward flight. There is at least one electric motor in each wing which drives at least one thrust generator. The thrust generators wind streams interact with all the vehicle lifting wings during vertical take off and landing to reduce the possibility to stall at low vehicle speed. The thrust generators may provide a combined thrust higher than the aircraft weight; the power required to drive the electric motors comes from the electric generator and the additional power required to provide a thrust higher than the aircraft weight comes from rechargeable electric energy storage devices such as batteries or supercapacitors. An active feedback system allows to control the rotational speed of each thrust generators and the tilt angles of each wing and the rudder on the basis of given flight inputs such as aircraft direction and speed.
TL;DR: In this article, the effect of removing the traditional peniche boundary layer spacer for low-speed wind tunnel tests of a flexible wing semi-span model has been implemented in the de Havilland wind tunnel at the University of Glasgow.
Abstract: Low-speed wind tunnel tests of a flexible wing semi-span model have been implemented in the $$9\times 7$$
ft de Havilland wind tunnel at the University of Glasgow. The main objective of this investigation is to quantify the effect of removing the traditional peniche boundary layer spacer utilised in this type of testing. Removal of the peniche results in a stand-off gap between the wind tunnel wall and the model’s symmetry plane. This offers the advantage of preventing the development of a horseshoe vortex in front of the model, at the peniche/wall juncture. The formation of the horseshoe vortex is known to influence the flow structures around the entire model and thus alters the model’s aerodynamic behaviours. To determine the influence of the stand-off gap, several gap heights have been tested for a range of angles of attack at $$Re=1.5\times 10^6$$
, based on the wing mean aerodynamic chord (MAC). Force platform data have been used to evaluate aerodynamic coefficients, and how they vary with stand-off heights. Stereoscopic Particle Imaging Velocimetry (sPIV) was used to examine the interaction between the tunnel boundary layer and model’s respective stand-off gap. In addition, clay and tuft surface visualisation enhanced the understanding of how local flow structures over the length of the fuselage vary with stand-off height and angle of attack. The presented results show that a stand-off gap of four-to-five times the displacement thickness of the tunnel wall boundary layer is capable of achieving a flow field around the model fuselage that is representative of what would be expected for an equivalent full-span model in free-air—this cannot be achieved with the application of a peniche.
1 May 2017
TL;DR: Adaptive control is applied to an unconventional aircraft, namely, a three-rotor flight vehicle, one of whose rotors can tilt about the longitudinal axis of the fuselage, to follow straight-line and circular flight trajectories.
Abstract: We apply adaptive control to an unconventional aircraft, namely, a three-rotor flight vehicle, one of whose rotors can tilt about the longitudinal axis of the fuselage. This combination of actuators has aerodynamic advantages but also poses challenges in terms of trimming the aircraft in order to balance the torque about the roll, pitch, and yaw axes. The paper uses retrospective cost adaptive control (RCAC) to trim the aircraft in hover as well as to follow straight-line and circular flight trajectories.
1 Jul 2017
TL;DR: A new code for a parametric and automatic Finite Element mesh generation of fuselages of civil transport aircraft is presented, providing a time saving and reliable tool in the conceptual design phase in order to evaluate stresses and deformations in the whole fuselage structure.
Abstract: In the present paper, a new code (named WAGNER) for a parametric and automatic Finite Element mesh generation of fuselages of civil transport aircraft is presented. The code aims at providing a time saving and reliable tool in the conceptual design phase in order to evaluate stresses and deformations in the whole fuselage structure; these data allows us a preliminary structural sizing to be used as a baseline for deeper investigations and to determine the empty weight of the fuselage in view of a preliminary prediction of the maximum take-off weight of the aircraft. As an example of application, two layouts have been analysed: a non conventional two aisle single-deck (SD) with 2-4-2 passengers abreast and a double-deck (DD) with 3-3 passengers abreast/deck. FEM results for two different load cases (combined loads at limit load factor and ultimate pressurization) with geometrical linear and non-linear solutions, are finally discussed.
TL;DR: In this article, the characteristics of a propulsive fuselage aircraft concept targeting entry-into-service year 203 were described, with a focus on the integration of synergistic airframe-propulsion system integration.
Abstract: As a novel approach toward the realization of synergistic airframe–propulsion system integration, the characteristics of a propulsive fuselage aircraft concept targeting entry-into-service year 203...
TL;DR: In this paper, the effect of luggage on the crashworthiness of a fuselage section with under-floor cargo compartment is investigated and a detailed nonlinear finite element models of an aircraft fuselage secti...
Abstract: This article investigates the effect of luggage on the crashworthiness of fuselage section with under-floor cargo compartment. Detailed nonlinear finite element models of an aircraft fuselage secti...