This work aims at evaluating the capabilities of several higher-order beam formulations for stress and dynamic analyses of layered sandwich structures. The structural models are conceived within the framework of the Carrera Unified Formulation (CUF) that allows one to generate (and compare) an infinite number of displacement fields. The number and the type of functions that are selected to generate the kinematic expansions are input parameters of the problem. Besides the well-known Taylor- and Lagrange-type expansions, great attention is paid to a new class of advanced higher-order zig-zag theories, which are written as combinations of continuous piecewise polynomial functions. Numerical simulations are performed on laminated and sandwich beams with very low length-to-depth ratio values. Also, structures with soft layers made of viscoelastic materials are considered to investigate the different dissipation mechanisms.
{"title":"Advanced Zig-Zag Beam Theories for Sandwich Structures Analyses","authors":"M. Filippi, E. Carrera","doi":"10.1115/IMECE2018-86783","DOIUrl":"https://doi.org/10.1115/IMECE2018-86783","url":null,"abstract":"This work aims at evaluating the capabilities of several higher-order beam formulations for stress and dynamic analyses of layered sandwich structures. The structural models are conceived within the framework of the Carrera Unified Formulation (CUF) that allows one to generate (and compare) an infinite number of displacement fields. The number and the type of functions that are selected to generate the kinematic expansions are input parameters of the problem. Besides the well-known Taylor- and Lagrange-type expansions, great attention is paid to a new class of advanced higher-order zig-zag theories, which are written as combinations of continuous piecewise polynomial functions. Numerical simulations are performed on laminated and sandwich beams with very low length-to-depth ratio values. Also, structures with soft layers made of viscoelastic materials are considered to investigate the different dissipation mechanisms.","PeriodicalId":119220,"journal":{"name":"Volume 1: Advances in Aerospace Technology","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123133742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Saxton, Soumyadip Patra, N. Xiros, M. Bernitsas, Hai Sun
Using data series obtained by experiments at the Marine Renewable Energy Laboratory of the University of Michigan, a Data-Driven Model is constructed for further investigation of the Process Dynamics and Control System Design and Configuration. This will enable advances in hydrokinetic energy harvesting using Vortex Induced Vibrations (VIV) and galloping, or more generally, Flow Induced Oscillations (FIO). Typically in such energy converters, one or more multiple bluff bodies, such as cylinders are suspended on springs in a water flow (currents, tides, rivers). In commonly encountered flows, oscillations are induced to the bluff rigid bodies due to vortex shedding in their wake, or due to lift instabilities in galloping, or both. These phenomena are dependent on stiffness, damping, mass ratio and the resulting vortex shedding frequency. The experiments in the cases investigated generated position signal recordings for one or two cylinders used as bluff bodies in FIO in a cross-flow. The position signals are used to set up a dynamic model. The model equation helps in gaining insight into the dynamics and underlying physics of the modeled FIO and can be used for Control System Tuning and Verification.
{"title":"System Identification of Hydrokinetic Energy Harvester Using Flow Induced Oscillations","authors":"R. Saxton, Soumyadip Patra, N. Xiros, M. Bernitsas, Hai Sun","doi":"10.1115/IMECE2018-87059","DOIUrl":"https://doi.org/10.1115/IMECE2018-87059","url":null,"abstract":"Using data series obtained by experiments at the Marine Renewable Energy Laboratory of the University of Michigan, a Data-Driven Model is constructed for further investigation of the Process Dynamics and Control System Design and Configuration. This will enable advances in hydrokinetic energy harvesting using Vortex Induced Vibrations (VIV) and galloping, or more generally, Flow Induced Oscillations (FIO). Typically in such energy converters, one or more multiple bluff bodies, such as cylinders are suspended on springs in a water flow (currents, tides, rivers). In commonly encountered flows, oscillations are induced to the bluff rigid bodies due to vortex shedding in their wake, or due to lift instabilities in galloping, or both. These phenomena are dependent on stiffness, damping, mass ratio and the resulting vortex shedding frequency. The experiments in the cases investigated generated position signal recordings for one or two cylinders used as bluff bodies in FIO in a cross-flow. The position signals are used to set up a dynamic model. The model equation helps in gaining insight into the dynamics and underlying physics of the modeled FIO and can be used for Control System Tuning and Verification.","PeriodicalId":119220,"journal":{"name":"Volume 1: Advances in Aerospace Technology","volume":"40 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131012128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
For aircraft, Airport facilities are indispensable infrastructure. Looking at the arrival and departure capabilities of Haneda / Narita airport which is said to be a crowded airport in japan, in 1992, Haneda Airport got 210,000 a year (40 departures / hours at departure and arrival), Haneda airport reached 130,000 a year, Totaling 340,000 times in total. In 2004 (2014), Haneda Airport had 447 thousand times and Narita airport had 300 thousand times, a total of 747 thousand times, showing more than doubling(1). Business opportunities of the air craft industry are expanding due to due to the start of sharing of Haneda’s new runway and new international passenger terminal. The development of modern IT promotes convenient air development of computers is greatly related to the transition from the Boeing 747 which was the theme this time to Boeing 777 promptly. I decided to investigate the fact that cooperation customers is changing in Boeing 747 and Boing 777.
{"title":"About the Immediate Shift From Large-Sized Machine Boeing 747 to Boeing 777","authors":"Masako Shishido","doi":"10.1115/IMECE2018-86770","DOIUrl":"https://doi.org/10.1115/IMECE2018-86770","url":null,"abstract":"For aircraft, Airport facilities are indispensable infrastructure. Looking at the arrival and departure capabilities of Haneda / Narita airport which is said to be a crowded airport in japan, in 1992, Haneda Airport got 210,000 a year (40 departures / hours at departure and arrival), Haneda airport reached 130,000 a year, Totaling 340,000 times in total. In 2004 (2014), Haneda Airport had 447 thousand times and Narita airport had 300 thousand times, a total of 747 thousand times, showing more than doubling(1). Business opportunities of the air craft industry are expanding due to due to the start of sharing of Haneda’s new runway and new international passenger terminal. The development of modern IT promotes convenient air development of computers is greatly related to the transition from the Boeing 747 which was the theme this time to Boeing 777 promptly. I decided to investigate the fact that cooperation customers is changing in Boeing 747 and Boing 777.","PeriodicalId":119220,"journal":{"name":"Volume 1: Advances in Aerospace Technology","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133168785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
To improve the airfoils performances placed in supersonic flow is proposed a method of optimization for their shapes, in order to minimize the effect of the landing vortices. The theoretical modeling starts with the Navier-Stokes equations applied for thin layers, supplemented with additional conditions related to the profile shape. For a proper estimation of efficiency and responses at different flow regime’s conditions, were considered four aerodynamics airfoils, with different shapes and functioning characteristics. Two of them are special shapes of supersonic profiles and the other two deduced by theoretical assessments with an efficient behavior at high Reynolds numbers. The main purpose of this selection was to identify the essential aspects needed to be considered in numerical modeling of the airfoil’s wing shapes, as to assure an optimization of their behavior for different flow conditions. In the supersonic flow, the cross-sections of the wings are thin profiles, mainly symmetric, as to reduce the drag coefficient and to maximize, as possible, the lift coefficient. A supplementary method for the shape calculation of the aerodynamic profiles with small curvature, based on the Fredholm integral equation of the second kind, with a good behavior in the supersonic flow, is presented. Some aspects referring to unsteady flows and air compressibility are considered, as to simulate as much as possible the real, natural conditions. All profiles were tested, firstly, into a subsonic wind tunnel at incidences between 00 – 40 for different values of wind velocity, and secondly, into a supersonic wind tunnel, at the same incidences. The objective was to better understand and analyze the main factors, which influence the aerodynamic of shapes with curvature, and to assure an optimization of their behavior. The purpose of testing these profiles was to estimate a solution to improve the main characteristics, especially into the trailing and leading edges zones. There were also considered the effects of the attack angle, the influence of the wind velocity, air viscosity, and the shape’s curvature, on the vortices development. The obtained results allow a better functioning in supersonic flow regime, by eliminating the adverse pressure gradient and the boundary layer separation, assuring an optimum behavior especially into the leading edge zone.
{"title":"Solution to Optimize the Airfoils Shapes Placed Into a Supersonic Viscous Flow","authors":"V. Radulescu","doi":"10.1115/IMECE2018-86781","DOIUrl":"https://doi.org/10.1115/IMECE2018-86781","url":null,"abstract":"To improve the airfoils performances placed in supersonic flow is proposed a method of optimization for their shapes, in order to minimize the effect of the landing vortices. The theoretical modeling starts with the Navier-Stokes equations applied for thin layers, supplemented with additional conditions related to the profile shape. For a proper estimation of efficiency and responses at different flow regime’s conditions, were considered four aerodynamics airfoils, with different shapes and functioning characteristics. Two of them are special shapes of supersonic profiles and the other two deduced by theoretical assessments with an efficient behavior at high Reynolds numbers. The main purpose of this selection was to identify the essential aspects needed to be considered in numerical modeling of the airfoil’s wing shapes, as to assure an optimization of their behavior for different flow conditions. In the supersonic flow, the cross-sections of the wings are thin profiles, mainly symmetric, as to reduce the drag coefficient and to maximize, as possible, the lift coefficient. A supplementary method for the shape calculation of the aerodynamic profiles with small curvature, based on the Fredholm integral equation of the second kind, with a good behavior in the supersonic flow, is presented. Some aspects referring to unsteady flows and air compressibility are considered, as to simulate as much as possible the real, natural conditions. All profiles were tested, firstly, into a subsonic wind tunnel at incidences between 00 – 40 for different values of wind velocity, and secondly, into a supersonic wind tunnel, at the same incidences. The objective was to better understand and analyze the main factors, which influence the aerodynamic of shapes with curvature, and to assure an optimization of their behavior. The purpose of testing these profiles was to estimate a solution to improve the main characteristics, especially into the trailing and leading edges zones. There were also considered the effects of the attack angle, the influence of the wind velocity, air viscosity, and the shape’s curvature, on the vortices development. The obtained results allow a better functioning in supersonic flow regime, by eliminating the adverse pressure gradient and the boundary layer separation, assuring an optimum behavior especially into the leading edge zone.","PeriodicalId":119220,"journal":{"name":"Volume 1: Advances in Aerospace Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130092838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This work explores the effects of geometrical nonlinearities in the vibration analysis of rotating structures and helicopter blades. Structures are modelled via higher-order beam theories with variable kinematics. These theories fall in the domain of the Carrera Unified Formulation (CUF), according to which the nonlinear equations of motion of rotating blades can be written in terms of fundamental nuclei, whose formalism is an invariant of the theory approximation. The inherent three-dimensional nature of CUF enables one to include all Green-Lagrange strain components as well as all coupling effects due to the geometrical features and the three-dimensional constitutive law. Numerical solutions are considered and opportunely discussed. Also, linearized and full nonlinear solutions for vibrating rotating blades are compared both in case of small amplitudes and in the large deflections/rotations regime.
{"title":"Nonlinear Dynamics of Rotating Structures and Helicopter Blades","authors":"M. Filippi, A. Pagani, E. Carrera","doi":"10.1115/IMECE2018-86786","DOIUrl":"https://doi.org/10.1115/IMECE2018-86786","url":null,"abstract":"This work explores the effects of geometrical nonlinearities in the vibration analysis of rotating structures and helicopter blades. Structures are modelled via higher-order beam theories with variable kinematics. These theories fall in the domain of the Carrera Unified Formulation (CUF), according to which the nonlinear equations of motion of rotating blades can be written in terms of fundamental nuclei, whose formalism is an invariant of the theory approximation. The inherent three-dimensional nature of CUF enables one to include all Green-Lagrange strain components as well as all coupling effects due to the geometrical features and the three-dimensional constitutive law. Numerical solutions are considered and opportunely discussed. Also, linearized and full nonlinear solutions for vibrating rotating blades are compared both in case of small amplitudes and in the large deflections/rotations regime.","PeriodicalId":119220,"journal":{"name":"Volume 1: Advances in Aerospace Technology","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117051324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Uddin, Pratik Sarker, C. Theodore, U. Chakravarty
Active vibration control is a widely implemented method for helicopter vibration control. Due to the significant progress in the microelectronics, this technique outperforms the traditional passive control technique due to the weight penalty and lack of adaptability for the changing flight conditions. In this paper, an optimal controller is designed to attenuate the helicopter rotor blade vibration. The mathematical model of the triply coupled vibration of the rotating cantilever beam is used to develop the state-space model of an isolated rotor blade. The required natural frequencies are determined by the modified Galerkin method and only the principal aerodynamic forces acting on the structure are considered. Linear quadratic regulator is designed to achieve the vibration reduction at the optimum level and the controller is tuned for the hovering and forward flight.
{"title":"Active Vibration Control of a Helicopter Rotor Blade by Using a Linear Quadratic Regulator","authors":"M. Uddin, Pratik Sarker, C. Theodore, U. Chakravarty","doi":"10.1115/IMECE2018-86319","DOIUrl":"https://doi.org/10.1115/IMECE2018-86319","url":null,"abstract":"Active vibration control is a widely implemented method for helicopter vibration control. Due to the significant progress in the microelectronics, this technique outperforms the traditional passive control technique due to the weight penalty and lack of adaptability for the changing flight conditions. In this paper, an optimal controller is designed to attenuate the helicopter rotor blade vibration. The mathematical model of the triply coupled vibration of the rotating cantilever beam is used to develop the state-space model of an isolated rotor blade. The required natural frequencies are determined by the modified Galerkin method and only the principal aerodynamic forces acting on the structure are considered. Linear quadratic regulator is designed to achieve the vibration reduction at the optimum level and the controller is tuned for the hovering and forward flight.","PeriodicalId":119220,"journal":{"name":"Volume 1: Advances in Aerospace Technology","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130341397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Passive vortex generators are widely used for heat and mass transfer enhancement in static mixers and heat exchangers. Trapezoidal vortex generators are used in the high efficiency vortex static mixer (HEV) because they generate a complex flow structure enhancing the transport phenomena. Moreover, vortex generators are used on airfoils and cars to delay or suppress flow separation. The flow past triangular and rectangular winglets was studied in the open literature showing good performance in enhancing the lift and drag coefficients. In the present study, a non-conventional vortex generator is proposed consisting on an inclined trapezoidal tab similar to that used in the HEV static mixer. In addition, the tab is perforated at its center (circular perforation). Inline array of several vortex generators are fixed on an airfoil and the drag and lift coefficients are analyzed for different geometries using computational fluid dynamics. Different cases are analyzed where the inclination angles of the vortex generators are changed and their effect is investigated. Furthermore, the effect of changing the size of the vortex generator is also assessed. The results are then compared to conventional vortex generators, mainly triangular winglets. The present results are validated against experimental and numerical data from the literature. The results show that the drag coefficient can be reduced with such vortex generators. They also show good agreement with experimental results for the lift coefficient.
{"title":"CFD-Based Aerodynamic Analysis of the Flow Past an Airfoil With Passive Trapezoidal and Perforated Vortex Generators","authors":"Charbel Bou-Mosleh, R. Himo, C. Habchi","doi":"10.1115/IMECE2018-87440","DOIUrl":"https://doi.org/10.1115/IMECE2018-87440","url":null,"abstract":"Passive vortex generators are widely used for heat and mass transfer enhancement in static mixers and heat exchangers. Trapezoidal vortex generators are used in the high efficiency vortex static mixer (HEV) because they generate a complex flow structure enhancing the transport phenomena. Moreover, vortex generators are used on airfoils and cars to delay or suppress flow separation. The flow past triangular and rectangular winglets was studied in the open literature showing good performance in enhancing the lift and drag coefficients. In the present study, a non-conventional vortex generator is proposed consisting on an inclined trapezoidal tab similar to that used in the HEV static mixer. In addition, the tab is perforated at its center (circular perforation). Inline array of several vortex generators are fixed on an airfoil and the drag and lift coefficients are analyzed for different geometries using computational fluid dynamics. Different cases are analyzed where the inclination angles of the vortex generators are changed and their effect is investigated. Furthermore, the effect of changing the size of the vortex generator is also assessed. The results are then compared to conventional vortex generators, mainly triangular winglets. The present results are validated against experimental and numerical data from the literature. The results show that the drag coefficient can be reduced with such vortex generators. They also show good agreement with experimental results for the lift coefficient.","PeriodicalId":119220,"journal":{"name":"Volume 1: Advances in Aerospace Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131619881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A composite material (CM) of periodic structure with the peristatic properties of constituents (see Silling, J. Mech. Phys. Solids 2000; 48:175–209) is analyzed by a generalization of the classical locally elastic computational homogenization to its peristatic counterpart. One introduces new volumetric periodic boundary conditions (PBC) at the interaction boundary of a representative unit cell (UC). A generalization of the Hill’s equality to peristatic composites is proved. The general results establishing the links between the effective moduli and the corresponding mechanical influence functions are obtained. The discretization of the equilibrium equation acts as a macro-to-micro transition of the deformation-driven type, where the overall deformation is controlled. Determination of the microstructural displacements allows one to estimate the peristatic traction at the geometrical UC’s boundary which is exploited for estimation of the macroscopic stresses and the effective moduli. One demonstrates computationally, through one-dimensional examples, the approach proposed.
一种具有周期性结构的复合材料(CM)，具有组分的蠕动特性(参见Silling, J. Mech。理论物理。固体2000;48:175-209)通过将经典的局部弹性计算均匀化推广到它的蠕动对应物来分析。在典型单元胞(UC)的相互作用边界上引入了新的体积周期边界条件(PBC)。证明了希尔方程在蠕动复合材料中的推广。得到了建立有效模量与相应力学影响函数之间联系的一般结果。平衡方程的离散化作为变形驱动型的宏观到微观转变，其中整体变形受到控制。微观结构位移的确定使人们能够估计几何UC边界的蠕动牵引力，该牵引力用于估计宏观应力和有效模量。通过一维的例子，对所提出的方法进行了计算论证。
{"title":"Computational Homogenization in Peristatics of Periodic Structure Composites","authors":"V. Buryachenko","doi":"10.1115/IMECE2018-86517","DOIUrl":"https://doi.org/10.1115/IMECE2018-86517","url":null,"abstract":"A composite material (CM) of periodic structure with the peristatic properties of constituents (see Silling, J. Mech. Phys. Solids 2000; 48:175–209) is analyzed by a generalization of the classical locally elastic computational homogenization to its peristatic counterpart. One introduces new volumetric periodic boundary conditions (PBC) at the interaction boundary of a representative unit cell (UC). A generalization of the Hill’s equality to peristatic composites is proved. The general results establishing the links between the effective moduli and the corresponding mechanical influence functions are obtained. The discretization of the equilibrium equation acts as a macro-to-micro transition of the deformation-driven type, where the overall deformation is controlled. Determination of the microstructural displacements allows one to estimate the peristatic traction at the geometrical UC’s boundary which is exploited for estimation of the macroscopic stresses and the effective moduli. One demonstrates computationally, through one-dimensional examples, the approach proposed.","PeriodicalId":119220,"journal":{"name":"Volume 1: Advances in Aerospace Technology","volume":"508 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132446289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The newly developed airplanes are using composite laminates to replace the metal alloys for different components, such as the fuselage and the wings. The major advantage of the composite materials is to reduce structural weight which results in reducing the fuel consumption. The aim of this project is to investigate the structural integrity of an airplane fuselage, which uses various types of carbon composite laminates under the static loading of the cabin pressurization. The research is performed using the finite element method and the HYPERMESH commercial software with a composite tool to change the thickness and the orientation of carbon fiber laminates used in the facesheet of the sandwich structure. Three different orientations/stacking sequence of the HexPly 8552 AS4 carbon fibers with two honeycomb cores: Hexagonal Al and Nomex. The results show that the composite material using the HexPly 8552 carbon fiber oriented at angle 30 and angle 45 and the Nomex Honeycomb core of a total laminate thickness of 15.875mm outperform all other thicknesses and orientations in regards to the static loading failure.
{"title":"Optimization of the Composite Airplane Fuselage for an Optimum Structural Integrity","authors":"A. Nagesh, Ola Rashwan, M. Abu-Ayyad","doi":"10.1115/IMECE2018-88215","DOIUrl":"https://doi.org/10.1115/IMECE2018-88215","url":null,"abstract":"The newly developed airplanes are using composite laminates to replace the metal alloys for different components, such as the fuselage and the wings. The major advantage of the composite materials is to reduce structural weight which results in reducing the fuel consumption. The aim of this project is to investigate the structural integrity of an airplane fuselage, which uses various types of carbon composite laminates under the static loading of the cabin pressurization. The research is performed using the finite element method and the HYPERMESH commercial software with a composite tool to change the thickness and the orientation of carbon fiber laminates used in the facesheet of the sandwich structure. Three different orientations/stacking sequence of the HexPly 8552 AS4 carbon fibers with two honeycomb cores: Hexagonal Al and Nomex. The results show that the composite material using the HexPly 8552 carbon fiber oriented at angle 30 and angle 45 and the Nomex Honeycomb core of a total laminate thickness of 15.875mm outperform all other thicknesses and orientations in regards to the static loading failure.","PeriodicalId":119220,"journal":{"name":"Volume 1: Advances in Aerospace Technology","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124292159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Chiavaroli, A. D. Martin, G. Evangelista, G. Jacazio, M. Sorli
The article deals with the architecture, performance, and experimental tests of a test bench for servo-actuators used in flight controls. After the state of the art on the subject, the innovative architecture of the built bench is described, in which flight control actuator under test and load actuator are not in line but mounted perpendicularly. The model of the bench actuating systems is then presented, consisting of the servo-controlled hydraulic actuator, load cell, speed transducer, angular position transducer of the coupling and pressure transducers. For each of these components the nonlinear multi-physics mechatronic model is described, according to the adopted solutions. The adopted force control algorithm is discussed, showing the integrative compensation on the action line and proportional-derivative on the feedback, with speed feedforward. The experimental tests carried out on the bench under stalled conditions are also presented, whose results concerning time and frequency responses are compared with those obtained through the linearized and non-linear numerical model. Finally, the non-linear models of the flight control actuator under test, controlled in position, and of the loading servo-actuator of the bench are joined together, and the results of various simulations are described.
{"title":"Real Time Loading Test Rig for Flight Control Actuators Under PHM Experimentation","authors":"P. Chiavaroli, A. D. Martin, G. Evangelista, G. Jacazio, M. Sorli","doi":"10.1115/IMECE2018-86967","DOIUrl":"https://doi.org/10.1115/IMECE2018-86967","url":null,"abstract":"The article deals with the architecture, performance, and experimental tests of a test bench for servo-actuators used in flight controls. After the state of the art on the subject, the innovative architecture of the built bench is described, in which flight control actuator under test and load actuator are not in line but mounted perpendicularly.\u0000 The model of the bench actuating systems is then presented, consisting of the servo-controlled hydraulic actuator, load cell, speed transducer, angular position transducer of the coupling and pressure transducers. For each of these components the nonlinear multi-physics mechatronic model is described, according to the adopted solutions. The adopted force control algorithm is discussed, showing the integrative compensation on the action line and proportional-derivative on the feedback, with speed feedforward.\u0000 The experimental tests carried out on the bench under stalled conditions are also presented, whose results concerning time and frequency responses are compared with those obtained through the linearized and non-linear numerical model.\u0000 Finally, the non-linear models of the flight control actuator under test, controlled in position, and of the loading servo-actuator of the bench are joined together, and the results of various simulations are described.","PeriodicalId":119220,"journal":{"name":"Volume 1: Advances in Aerospace Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132744680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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