Honeycomb Sandwich Plate Research Articles

Dynamic Analysis of Hexagon Honeycomb Sandwich Plate Resting on Elastic Foundations

Dynamic analysis of hexagon honeycomb sandwich plate resting on elastic foundations are presented. Modeling is formed by 3 layers, in which core layer is hexagon honeyconb and facesheet layers is isotropic material. The Reddy’s first order shear deformation plate theory and Galerken method are used to investigate the influnce of elastic foundations, geometrical parameters and material properties of hexagon honeycomb on the deflection – time curve. The value of the natural frequency was compared to the results reported in other works forevaluating the acuracy of used method.

Modal analysis of honeycomb panel satellite structure based on MSC Apex

Modal analysis plays an important role in the process of Satellite structure development. In this paper, the honeycomb sandwich plate and the satellite structure are taken as the research objects, and the corresponding finite element models are established. The analysis results of the actual modeling of honeycomb plate and the equivalent modeling of sandwich sandwich plate are obtained, and the fundamental frequency deviation of the whole satellite structure is discussed when the equivalent correction coefficient γ of honeycomb plate is different. The results show that the maximum relative error of the modal frequency between the equivalent method of sandwich sandwich plate and the actual modeling is 2.8%. Therefore, the equivalent method can be applied to large-scale finite element analysis and calculation, and the calculation efficiency can be improved. When the value of γ is 0.4∼0.6, the vibration modes of the whole satellite structure are basically consistent, and the maximum fundamental frequency difference is 10%. The results can evaluate the accuracy of the sandwich sandwich plate equivalent method for satellite mechanical analysis.

Buckling Stability and Vibration Characteristics of Functionally Graded Graphene Platelet-Reinforced Composites Multi-Arc Concave Honeycomb Sandwich Panels Under Thermal Loading

The utilization of functionally graded graphene platelet-reinforced composites (FG-GPLRC) and honeycomb sandwich constructions is prevalent in the field of engineering. Therefore, it is crucial to investigate the buckling and vibration properties of these materials under heat circumstances. This paper specifically focuses on the vibration and thermal buckling characteristics of a novel multi-arc concave honeycomb sandwich plate (MACHSP) equipped with an adjustable positive-negative Poisson’s ratio. The governing equations of motion for the system are derived based on the first-order shear deformation theory in conjunction with Hamilton’s principle. The formulation of the system’s characteristic equation involves the establishment of displacement functions that satisfy distinct boundary conditions. Using computational programming, natural frequencies, mode shapes, and critical buckling temperatures of MACHSP with three different FG-GPLRC distributions under thermal influences are determined. Subsequently, these results are compared with outcomes from finite element simulations and findings from previously published literature. Additionally, the amplitude-frequency response characteristics of the structure under harmonic excitation are analyzed, followed by a discussion of the impact of structural parameters on its buckling and vibration characteristics. The results indicate that the established theoretical model for predicting the buckling and vibration characteristics of MACHSP with FG-GPLRC distribution aligns well with simulation models and prior research. In contrast to solid plates, MACHSP not only achieves a substantial reduction in weight but also demonstrates a significant increase in natural frequency. Furthermore, graphene platelets have the potential to enhance the structure’s natural frequency values and critical buckling temperatures. Lastly, various structural parameters exert a notable influence on the structure’s performance.

Experimental and numerical study of effecting core configurations on the static and dynamic behavior of honeycomb plate with aluminum material

The sandwich panel incorporated a honeycomb core, a widely utilized composite structure recognized as a fundamental classification of composite materials. Comprised a core resembling a honeycomb, possessing thickness and softness, and is flank by rigid face sheets that sandwich various shapes and materials. This paper presents an examination of the static and dynamic analysis of lightweight plates made of aluminum honeycomb sandwich composites. Honeycomb sandwich plate samples are 300 mm long, and 300 mm wide, the heights of the core have been varied at four values ranging from 10 to 25 mm. The honeycomb core is manufactured from Aluminum material by using a novel technique namely resistance spot welding (RSW) instead of using adhesive material, which is often used when an industrial flaw is detected. Numerical optimization based on response surface methodology (RSM) and design of experiment software (DOE) was used to verify the current work. A theoretical examination of the crashworthiness behavior (maximum bending load, maximum deflection) and vibration attributes (natural frequency, damping ratio, transient temporal response) of honeycomb sandwich panels with different design parameters was also carried out. In addition, the finite element method-based ANSYS software was used to confirm the theoretical conclusions. The findings of the present work showed that the relationship between the natural frequency, core height, and cell size is direct. In contrast, the relationship between the natural frequency and the thickness of the cell wall is inverse. Conversely, the damping ratio is inversely proportional to the core height and cell size but directly proportional to the thickness of the cell wall. The study indicates that altering the core height within 10–25 mm leads to a significant increase of 82 % in the natural frequency and a notable decrease of 49 % in the damping ratio. These findings are based on a specific cell size value of 0.01 m and a cell wall thickness of 0.001 m. Also, the results indicate that for a given set of cell wall thickness and size values, an increase in core height from (0.01–0.025) m, leads to a reduction of the percentage of maximum response approximately 76 %. Conversely, the increasing thickness of the wall of cell wall, ranging 0.3–0.7 mm with a constant core height equal to 0.015 m, resulted in a de crease of maximum transient response by 7.8 %.

Nonlinear free vibration analysis of internal thickness-tapered multi-layered composite rectangular plates undergoing moderately large deflections

Thickness-tapering in multi-layered composites is achieved by terminating the plies at discrete locations. This allows for effective material utilization and significant weight savings and is adopted in applications involving multi-layered composites that demand variation in thickness such as helicopter yokes, flexbeams and rotor blades, aircraft wing-skin structures and turbine blades. In the present work, the nonlinear free vibration of such tapered composites undergoing moderately large deflections is investigated for the first time. A general nonlinear finite element formulation for tapered multi-layered composite plates based on Reddy's higher-order shear deformation theory and considering Von Karman nonlinearity is developed. Newton–Raphson scheme in conjunction with Newmark time-integration technique is employed to obtain the time response. The developed model is validated against available results in the literature and through experimentally obtained linear natural frequencies of a honeycomb sandwich plate with tapered face sheets. Parametric studies are conducted to deeply understand the nonlinear dynamic behaviour of tapered composite structures. The investigation reveals that tapered multi-layered composite plates exhibit higher nonlinearity compared to uniform plates thus necessitating the consideration of nonlinear effects in the analysis of such structures.

Sound transmission loss behavior of honeycomb sandwich plate structure under thermal loading

This paper presents an accurate and analytical method for investigating the sound transmission loss (STL) characteristics of honeycomb sandwich plate structure subjected to combined thermal and acoustic excitation. In the analysis, the governing equations of sandwich plate structure in thermal environments are established by first order shear deformation theory. Two types of thermal conditions with and without heat flux are considered. The fluid-structure coupling interaction between the plate structure and acoustic excitation is described analytically by applying velocity continuity condition at fluid-structure interfaces. By using the modal expansion approach, the sound transmission loss is described analytically. The experimental measurements of honeycomb sandwich plate are carried out to validate the theoretical model, and good agreement is achieved. Finally, the influences of honeycomb core dimensions, material parameter and temperature distribution on sound transmission loss behavior of honeycomb sandwich structure have been investigated. It has found that the resonance dips of STL curves move to higher frequencies with the increase of ratio of elastic modulus and honeycomb core wall thickness, but the increase of the honeycomb core side length causes the resonance dips to move to low frequencies. The magnitudes of the STL curves are found to be decreasing with increase of temperature values.

Structural optimization of a small earth remote sensing satellite

Structural sizing optimization is a crucial step in the process of modern satellite structural design. It warrants minimizing the satellite structural mass while improving the overall quality and reliability of such design. This article discusses thoroughly the structural optimization of a small earth remote sensing satellite whose primary structure is based upon aluminum honeycomb sandwich plates. A novel contribution has been conducted in extending the optimization problem to include the main static and dynamic loads acting simultaneously on the satellite during launch phase utilizing the results of static, buckling, modal, and harmonic response analyses. The small satellite optimization process starts initially with formulating the optimization problem based upon the structural analyses results. Subsequently, miscellaneous optimization techniques utilizing ANSYS workbench capabilities represented in “DesignXplorer” module are employed. Finally, the results are compared with other results obtained from a MATLAB code based upon both genetic and sequential quadratic programming algorithms. The optimization process leads to approximately 30% mass reduction in the proposed satellite structure. A special attention is drawn towards meta-models due to their capabilities in solving complex structural models with a reasonable wall-clock time.

Free vibration and nonlinear dynamic response of sandwich plates with auxetic honeycomb core and piezoelectric face sheets

This article analyses the nonlinear dynamic behavior and the free vibration of a piezoelectric auxetic honeycomb sandwich plate resting on a Pasternak elastic substrate. The plate includes two face sheets of piezoelectric material and an auxetic honeycomb core with a negative Poisson ratio. The first-order shear deformation plate theory, together with the von Kármán type nonlinear strain-displacement relationship, is used to establish the nonlinear equations of motion. Linear electric potential change with piezoelectric layer thickness is assumed. Two types of boundary conditions, namely immovable and movable simply supported, are considered. The displacement-time and acceleration-displacement curves under dynamic loads are determined by using the Galerkin and Runge-Kutta fourth-order methods. Verification examples have been performed and confirmed the accuracy of the model. Finally, several novel investigations have been conducted to evaluate the effect of material, geometrical parameters, and elastic substrate coefficients on the frequency and nonlinear dynamic characteristics of piezoelectric auxetic honeycomb sandwich plates for both open-circuit and closed-circuit operation.

An analytical model for the static behaviour of honeycomb sandwich plates with auxetic cores using higher-order shear deformation theories

AbstractThis paper presents an analytical model to investigate the static behaviour of sandwich plates comprised of two isotropic face sheets and a honeycomb core. Through-thickness transverse shear stresses were considered using a unified displacement field with which various plate theories were implemented, i.e., exponential, third-order, hyperbolic, sinusoidal, fifth-order, Mindlin, and the classic plate theory. The equilibrium equations of a simply-supported sandwich panel were derived using the principle of virtual work and Navier solution was obtained under static transverse loading. After validating of the model, various mechanical and geometrical parameters were varied to characterise the behaviour of the structure under regular and auxetic response. It was found that the auxeticity of the core strongly affects the mechanical response, e.g., in controlling deflection, in-plane anisotropy, and Poisson’s ratio. Cell wall angle was found to be most critical parameter that can be used to adjust anisotropy, out-of-plane shear modulus, transverse shear stress distribution, and deflection of the panel. Also the cell aspect ratio controls the sensitivity of the core response to other geometrical variations. In terms of the higher-order theories, the deflection-dependent parameter of the unified formulation seems to have more control of maximum deflection compared to independent rotations. Auxeticity of the core showed some benefits in controlling anisotropy, deflection and providing additional out-of-plane shear rigidity. Overall, since there is not one-to-one relationship between specific values of Poisson’s ratio, anisotropy, and shear rigidity, careful design considerations must be invested to obtain a correct mechanical response.

Numerical and experimental investigation for flexural response of Kevlar short fiber tissue/carbon fiber belts toughened honeycomb sandwich plate

This paper investigates the flexural behavior of honeycomb sandwich panels with a toughened/untoughened interface using carbon fiber belt and short aramid fiber tissues. In the first part of the paper, bending response analysis of carbon fiber aluminum honeycomb sandwich plates with an untoughened interface is done using finite element-based first-order shear deformation theory. In the second part, experimental analysis is done to examine the effect of loading rates on the mechanical characteristics of plain and toughened sandwich panels using a three-point bending test. Four types of interface toughening are used as unidirectional and bi-directional stitches of carbon fiber belts, Kevlar short-fiber tissues, and carbon fiber belts combined with Kevlar short-fiber tissues. Experimental result shows that interface toughening improves the maximum load and energy absorbed by sandwich specimens for all loading rates. A scanning electron microscope is used to observe and analyze the failure mode and mechanism of strengthening the interface. It is observed that the stitch of the carbon fiber belt increases the adhesion contact between face sheets and core leading to prevent interfacial debonding. The peak load and energy absorptions of carbon fiber belts toughened interface sandwich are increased by 51 % and 42.5 %, respectively, compared with that of the plain sandwich by a small increment of weight (14%).

Finite Element Simulation Analysis of Aluminum Honeycomb Sandwich Plate Penetration of Aircraft Under High-Speed Bird Impact

In the process of flight, the penetration caused by bird strikes will cause a significant decrease in the bearing capacity of the material, or even complete loss, which will lead to the accident of the aircraft. Therefore, it is of great significance to study the mechanical properties of aluminum honeycomb sandwich panels at different angles of high-speed bird impact. In this paper, finite element software is used to numerically analyze the penetration process. In this paper, the impact test of the aluminum honeycomb sandwich panel was carried out at 90°, 75°, 60° and 45° at the speed of 170m/s by using 1.8kg birdshot. Through finite element simulation analysis of the damage process, contact force and energy absorption rate of the aluminum honeycomb sandwich panel, it is found that when the bird projectile penetrates the aluminum honeycomb sandwich plate, the aluminum honeycomb sandwich in the impact center will be seriously deformed, torn and penetrated and failed. The angle of bird impact has a great influence on the peak contact force and the decay rate of contact force, the energy absorption effect increases exponentially with the decrease of the angle.

Damage Imaging Identification of Honeycomb Sandwich Structures Based on Lamb Waves.

In the field of structural health monitoring, Lamb Wave has become one of the most widely used inspection tools due to its advantages of wide detection range and high sensitivity. In this paper, a new damage detection method for honeycomb sandwich structures based on frequency spectrum and Lamb Wave Tomography is proposed. By means of simulation and experiment, a certain number of sensors were placed on the honeycomb sandwich plate to stimulate and receive the signals in both undamaged and damaged cases. By Lamb Wave Tomography, the differences of signals before and after damage were compared, and the damage indexes were calculated. Furthermore, the probability of each sensor path containing damage was analyzed, and the damage image was finally realized. The technology does not require analysis of the complex multimode propagation properties of Lamb Wave, nor does it require understanding and modeling of the properties of materials or structures. In both simulation and experiment, the localization errors of the damage conform to the detection requirements, thus verifying that the method has certain feasibility in damage detection.

Analytical and experimental study on honeycomb sandwich plates reinforced by ring beam of satellites

The equivalent parameters of hexagon aluminum honeycombs are work out with the theories of sandwich plates in this paper. The honeycomb sandwich plate reinforced by ring beam applied with static load is simulated by the finite element model of honeycomb sandwich plates, which is validated by static test. The research results show that the numerical calculation error of the honeycomb sandwich plate is less than 10% compared with test results, which is acceptable for an engineering project, and the mechanical behavior of the honeycomb sandwich plate can be described in detail. Thus, the method of equivalent honeycomb parameter is proved to be effective for the design and analysis of honeycomb sandwich plates. The influence of equivalent elasticity modulus and equivalent shear modulus to honeycomb sandwich plates can be reflected exactly from the results which are figured out with the equivalent theories of sandwich plates. The assembly clearance and assembly accuracy have a significant influence to the test results of honeycomb sandwich plates, which is obvious especially at a lower load level.

Experimental study and modeling analysis of planar compression of composite corrugated, lattice and honeycomb sandwich plates

Experimental study and modeling analysis of planar compression of composite corrugated, lattice and honeycomb sandwich plates

Ballistic performance of ultralight multifunctional cellular sandwich plates with UHMWPE fiber metal laminate skins

While an ultralight sandwich construction with cellular core can be tailored to exhibit superior load-bearing capability and blast resistance, its ballistic performance is typically inferior to its equivalent monolithic counterpart. To improve the projectile penetration resistance while maintaining the capability of load bearing and blast mitigation, this work proposed a multifunctional sandwich plate with ultra-high molecular weight polyethylene (UHMWPE) fiber metal laminate (FML) skins and aluminum honeycomb core. A combined experimental and numerical approach was employed to quantify the ballistic performance, assess the penetration process, and reveal the underlying mechanisms of the novel sandwich construction. In addition to ballistic resistance, its performance under three-point bending as well as impulsive shock loading was also assessed for multifunctional applications. Relative to all-metallic honeycomb sandwich plate having identical areal density, incorporating UHMWPE composite layers into the skin improved significantly the penetration resistance: the failure mode of the laminate skin was changed from local shear-plugging to global dishing and cracking, enabling enhanced energy absorption of the thin metallic (titanium) layers. Moreover, the use of UHMWPE FML skin for sandwich construction led to not only significantly enhanced bending capacity but also reduced maximum deflection under impulsive shock loading. Hence, the proposed cellular sandwich plate with UHMWPE FML skins can be designed as ultralight multifunctional structure with simultaneous load-bearing and blast/ballistic resistant capabilities.

Experimental, numerical and analytical study to develop a design method for bending and shear resistances of 3D printed beetle elytron inspired sandwich plate (beetle elytron plate)

Beetle elytron plate (BEP) is a new type of sandwich structure inspired by the internal architecture of beetle elytra and characterized by trabeculae in the core to achieve better mechanical resistance compared to conventional honeycomb sandwich plate under lateral loads. To take advantage of this improved performance in design, this paper presents, for the first time, a series of static four-point bending and shear tests for buckling and post-buckling behaviour of small-scale 3D printed BEPs until failure. Tensile coupon tests were also carried out on the 3D printed material. The experimental results are then used to validate ABAQUS numerical modelling that previously could only be partially carried out due to a lack of experimental data. The test results confirm large increases in BEP resistances compared to conventional honeycomb sandwich plates of the same dimensions. The observed BEP failure mode under bending is post-buckling of the compressive skin. Assuming that the post-buckling stress of BEP can be calculated in the same way as conventional sandwich plate, and making use of the elastic–plastic buckling stress solution for BEP that had previously been proposed by the authors, this paper proposes a simple method to calculate the post-buckling stress of BEP for design purpose. For shear resistance, the shear buckling stress of the trabecular core of BEP can be calculated in the same way as for conventional honeycomb sandwich plate except for using the web width between the near edges of the two adjacent trabeculae. The proposed calculation methods give results in good agreement with experimental results, with the maximum difference being 8%. The difference would be even lower if the smooth 3D printed surface is under compression.

Free vibration behaviours of composite sandwich plates with reentrant honeycomb cores

The free vibration behaviours of carbon fiber composite sandwich plates with reentrant honeycomb cores were explored by experiment, theory and finite element method (FEM) in present study. The composite sandwich plates with reentrant honeycomb cores were designed and fabricated through hot-press and secondary forming technology. The modal characteristics of composite auxetic honeycomb sandwich plates were tested under simply supported boundary conditions. Furthermore, the influences of relative densities and dimensions on the natural frequencies of composite auxetic honeycomb sandwich plates were studied. The equivalent moduli of the unit cell of reentrant hexagonal core were deduced. The free vibration control equation was derived to gain the natural frequencies of the sandwich plates by Zig-Zag theory. The theoretical results of the natural frequencies were obtained and compared with the experimental results and finite element calculation results. The results showed that the theory and FEM could estimate the natural frequencies of this kind of sandwich plates accurately. The natural frequencies of the sandwich plates raised as the increasing of relative densities and influenced by dimensions of the core.

Synthetical vibration reduction of the nonlinear acoustic metamaterial honeycomb sandwich plate

Light-weight and high-stiffness honeycomb sandwich plates are widely used in high- speed vehicles. Suppressing their low-frequency and broadband vibration is significant for improving safety and reducing noise, but remains challenging with limited mass cost. Bandgaps and chaotic band in nonlinear acoustic metamaterials (NAMs) offer an effective way for vibration reduction. This paper conceives a NAM sandwich plate and studies its vibration reduction properties based on numerical and experimental methods. We establish its nonlinear finite element model based on the equivalent homogeneous model and experiments. The influences of the resonator distribution, nonlinear stiffness, resonant frequencies, mass, amplitude and structural plate parameters on its vibration are thoroughly analyzed to achieve the best performance. Then, we manufacture an optimized NAM plate and experimentally demonstrate that all resonances of the high-stiffness NAM plate below 800 Hz are greatly reduced with only 17.7 % attached mass; particularly, the first low-frequency resonance at 93 Hz is reduced by 20 dB. This shows that the NAM strategy can robustly and effectively suppress the low-frequency and broadband vibration of the light-weight and high-stiffness plates with small mass cost, a synthetical performance desired for broad potential applications. The models, regularities, designs and experiments can also enlighten more studies on relate topics.

Free vibration analysis of an auxetic honeycomb sandwich plate placed at the wall of a fluid tank

This paper presents a parametric investigation of the free vibration characteristics of an auxetic honeycomb sandwich plate mounted at the wall of a liquid tank. Frostig's second model is utilized in the core, while first-order shear deformation theory (FSDT) is applied to the face sheets. The honeycomb core is homogenized using one of the newest revised models (Tornabene's model), and the fluid is assumed to be ideal. The governing equations of motion are derived using Hamilton's principle and solved using the Galerkin method. Present solution method, honeycomb core homogenization formula, and mathematical framework for the fluid-sandwich plate interaction are verified using 3D Finite Element Analysis (FEA). Finally, the wet fundamental frequency is investigated with geometric parameters such as the ratio of tank dimensions to the plate length, fluid height from the plate's bottom edge, plate location at the tank wall, and honeycomb cell geometry. According to the results of this study, the thickness of the face sheet and the cell wall enhance the wet fundamental frequency, while the cell aspect ratio decreases it.

Elastic–plastic buckling behaviour of beetle elytron plate with simple, fixed and flexible core supports

Beetle elytron plate (BEP) is a new type of sandwich structure inspired by the internal architecture of beetle elytra and characterised by trabeculae in the core to achieve higher load bearing capacity compared to the basic conventional honeycomb sandwich plate. This paper investigates elastic–plastic buckling behaviour of the compressive skin of BEP with flexible core. The development is based on adapting existing solutions for relevant structures through the following three transformation steps: (1) obtaining the elastic–plastic buckling stresses of BEP with simple and fixed supports by extending respective solutions for conventional sandwich plate; (2) modifying the elastic buckling stress solution for conventional sandwich plate with flexible core to BEP with flexible core through replacement of deformation shape functions; (3) assuming that the interpolation function between simple and fixed supports for BEP with flexible core for elastic buckling stresses is applicable to elastic–plastic buckling stresses. Despite complexity of the problem and simplification in the above mentioned transformation steps, the proposed analytical method is shown to be quite accurate by comparison against numerical simulation results using a validated ABAQUS model for a variety of BEP geometries (such as trabecular diameter, slenderness values of the compressive skin and the core layer) and different material properties as represented by Ramberg–Osgood model covering the entire spectrum of elastic buckling to plastic behaviour, with the maximum difference between the proposed analytical model and numerical simulation results being 7%.