scholarly journals Investigation of vibration transmissibility for paper honeycomb sandwich structures with various moisture contents

2019 ◽  
Vol 20 (1) ◽  
pp. 108
Author(s):  
Dong-Mei Wang ◽  
Rui Yang
Keyword(s):  
Moisture Content ◽  
Sandwich Structure ◽  
Sandwich Structures ◽  
Absorption Capacity ◽  
Cell Length ◽  
Vibration Prediction ◽  
Honeycomb Sandwich ◽  
Vibration Transmissibility ◽  
Paper Honeycomb ◽  
Honeycomb Sandwich Structure

Vibration transmissibility is an important factor to characterize the vibration absorption performance of cushioning packaging materials during transportation. Reasonable prediction of vibration transmissibility can guide antivibration design and reduce packaging cost. As a kind of green cushioning material, paper honeycomb sandwich structure is widely used in transport packaging because of its good machinability. But at the same time, it also has strong water absorption capacity. To a great extent, the vibration transmissibility of paper honeycomb sandwich structure may be affected by ambient humidity. In this research, the vibration transmissibility of paper honeycomb sandwich structures with various structure sizes under different humidity was tested by sine frequency sweep experiments. The rule of maximal vibration transmissibility with moisture content, cell length of honeycomb, and thickness of sandwich structure was analyzed. The results show that the maximal vibration transmissibility of paper honeycomb sandwich structure increases with the increase of moisture content, cell length of honeycomb, and thickness of sandwich structure. In order to construct the relationship between maximal vibration transmissibility and various factors, the moisture content was standardized. Finally, the maximal vibration transmissibility evaluation equation of paper honeycomb sandwich structure containing standardized moisture content and size of sandwich structure was obtained, which is of some reference value for vibration prediction of paper honeycomb sandwich structures.

Maximum Vibration Transmissibility of Paper Honeycomb Sandwich Structures

2019 ◽  
Vol 19 (06) ◽  
pp. 1971003
Author(s):  
Rui Yang ◽  
Dong-Mei Wang ◽  
Ning Liang ◽  
Yan-Feng Guo
Keyword(s):  
Sandwich Structure ◽  
Sandwich Structures ◽  
Three Dimensional ◽  
Polynomial Equation ◽  
Static Stress ◽  
Cell Length ◽  
Honeycomb Sandwich ◽  
Vibration Transmissibility ◽  
Frequency Sweep Test ◽  
Paper Honeycomb

The maximum vibration transmissibility of paper honeycomb sandwich structures with different sizes of honeycomb core under various static stresses was investigated using the sine frequency sweep test. The effects of the cell length of the honeycomb, the thickness of the sandwich structure, and the static stress on the maximum vibration transmissibility were evaluated and a linear polynomial equation for evaluating the maximum vibration transmissibility was obtained. The results show that the maximum vibration transmissibility increases steadily with the increase in the cell length of the honeycomb, the thickness of the sandwich structure, and the static stress. The proposed equation for the maximum vibration transmissibility is suitable for predicting the maximum vibration transmissibility of paper honeycomb sandwich structures. In addition, the fitted three-dimensional diagrams of the effects of the factors on the maximum vibration transmissibility derived from the evaluation equation were shown to be in good agreement with the experimental results.

Detection of Unbonds in Honeycomb Sandwich Structure Using Lock-In Thermography

2010 ◽  
Vol 97-101 ◽  
pp. 4363-4366
Author(s):  
Hui Liu ◽  
Jun Yan Liu ◽  
Yang Wang ◽  
Hui Juan Li
Keyword(s):  
Sandwich Structure ◽  
Sandwich Structures ◽  
Modulation Frequency ◽  
Influencing Factor ◽  
Face Sheet ◽  
Honeycomb Core ◽  
Honeycomb Sandwich ◽  
Testing Technology ◽  
Lock In ◽  
Honeycomb Sandwich Structure

Lock-in thermography (LT), that is active infrared testing technology, mainly includes optical lock-in thermography (OLT) and ultrasound lock-in thermography (ULT). LT can be used to detect unbonds between honeycomb core and face sheet of sandwich structures. However, modulation frequency is an important influencing factor. In this paper, the principles of LT are represented, in experimental detections of simulated unbonds in honeycomb sandwich structures with Al-face sheet and CFRP-face sheet using OLT and ULT, detectability of OLT and ULT is compared and analyzed, effect of modulation frequency is researched and the optimal frequencies are obtained.

scholarly journals Structural geometries and mechanical properties of vertebral implant with honeycomb sandwich structure for vertebral compression fractures: a finite element analysis

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Yuan Guo ◽  
Jing Liu ◽  
Xushu Zhang ◽  
Zejun Xing ◽  
Weiyi Chen ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Sandwich Structure ◽  
Sandwich Structures ◽  
Peak Stress ◽  
Axial Deformation ◽  
The Finite Element Method ◽  
Honeycomb Sandwich ◽  
Honeycomb Sandwich Structure ◽  
Anterior Posterior

Abstract Background Because of osteoporosis, traffic accidents, falling from high places, and other reasons, the vertebral body can be compressed and even collapse. Vertebral implants can be used for clinical treatment. Because of the advantages of honeycomb sandwich structures, such as low cost, less material, light weight, high strength, and good cushioning performance. In this paper, the honeycomb sandwich structure was used as the basic structure of vertebral implants. Methods The orthogonal experiment method is applied to analyse the size effect of honeycomb sandwich structures by the finite element method. Based on the minimum requirements of three indexes of peak stress, axial deformation, and anterior–posterior deformation, the optimal structure size was determined. Furthermore, through local optimization of the overall structure of the implant, a better honeycomb sandwich structure vertebral implant was designed. Results The optimal structure size combination was determined as a panel thickness of 1 mm, wall thickness if 0.49 mm, cell side length of 1 mm, and height of 6 mm. Through local optimization, the peak stress was further reduced, the overall stress distribution was uniform, and the deformation was reduced. The optimized peak stress decreased to 1.041 MPa, the axial deformation was 0.1110%, and the anterior–posterior deformation was 0.0145%. A vertebral implant with good mechanical performance was designed. Conclusions This paper is the first to investigate vertebral implants with honeycomb sandwich structures. The design and analysis of the vertebral implant with a honeycomb sandwich structure were processed by the finite element method. This research can provide a feasible way to analyse and design clinical implants based on biomechanical principles.

Experiment and Simulation on the Flexural Properties of Fiber-Paper Honeycomb Sandwich Structure Compound Panel

2012 ◽  
Vol 200 ◽  
pp. 80-85
Author(s):  
Xiao Jun Yang ◽  
Qing Shan Lan ◽  
Yu Ning Zhong ◽  
Li Xia Zeng
Keyword(s):  
Sandwich Structure ◽  
Optimization Design ◽  
Sandwich Panel ◽  
Flexural Properties ◽  
Engineering Software ◽  
Equivalent Models ◽  
Bending Load ◽  
Honeycomb Sandwich ◽  
Paper Honeycomb ◽  
Honeycomb Sandwich Structure

Two equivalent models based on sandwich panel theory and equivalent panel theory were discussed in this paper. By analyzing the performance of fiber - paper honeycomb sandwich structure compound panel by bending load, the computational results are in accordance with test and Engineering software ANSYS. Therefore, it shows that the finite element equivalent models are reasonable and practical for the optimization design of fiber - paper honeycomb sandwich composites.

Experiment and Simulation on Natural Frequency of Fiber-Paper Honeycomb Sandwich Structure Composites

2011 ◽  
Vol 101-102 ◽  
pp. 360-364 ◽  
Author(s):  
Xiao Jun Yang ◽  
Qing Shan Lan ◽  
Yu Ning Zhong
Keyword(s):  
Sandwich Structure ◽  
Optimization Design ◽  
First Order ◽  
Finite Element Software ◽  
Honeycomb Sandwich ◽  
Vibration Experiment ◽  
Paper Honeycomb ◽  
Result Analysis ◽  
Equivalent Method ◽  
Honeycomb Sandwich Structure

The theory of natural frequencies were acquired from vibration experiment, meanwhile, the first order frequencies of honeycomb sandwich structure composites were obtained by using the sandwich laminboard theory and equivalent panel theory via the finite element software ANSYS. The simulation results were compared to the experiment results to get the error of calculation of the two different equivalent methods, thereby we can select more appropriate equivalent method to ensure the veracity of the result analysis and provide a reference for the optimization design of the fiber-paper honeycomb sandwich structure composites.

Experimental and numerical study for effective thermal conductivity of metallic honeycomb sandwich structures

2020 ◽  
pp. 109963622093353
Author(s):  
Rongnan Yuan ◽  
Shouxiang Lu
Keyword(s):  
Thermal Conductivity ◽  
Effective Thermal Conductivity ◽  
Sandwich Structure ◽  
Sandwich Structures ◽  
Numerical Study ◽  
Heat Transfer Process ◽  
Heat Radiation ◽  
Honeycomb Sandwich ◽  
Essential Parameter ◽  
Honeycomb Sandwich Structure

Effective thermal conductivity is an essential parameter to investigate thermal properties of metallic honeycomb sandwich structures. And it cannot be measured by traditional methods due to sandwich structure imbedded with air. A practical experimental equipment was designed to evaluate the value under different temperature from 100°C to 400°C. And it was found that the value of effective thermal conductivity can also be calculated by knowing the thermal conductivity of the reference, thickness of the reference and the slope and intercept of temperature in different layers. Meanwhile, numerical simulation was conducted and the results agreed well with that achieved by experiment. Also, the value of effective thermal conductivity calculated by experiment is close to the value calculated by Swann-Pittman empirical equation. And the method is not limited in metallic honeycomb sandwich structure while it can be applied in most structures with amounts of air. On that basis, heat transfer process of the structure is discussed including heat conduction, heat convection and heat radiation.

Ballistic performance of honeycomb sandwich structures reinforced by functionally graded face plates

2017 ◽  
Vol 21 (1) ◽  
pp. 211-229 ◽  
Author(s):  
Recep Gunes ◽  
Kemal Arslan ◽  
M Kemal Apalak ◽  
JN Reddy
Keyword(s):  
Sandwich Structure ◽  
Sandwich Structures ◽  
Threshold Energy ◽  
Functionally Graded ◽  
Honeycomb Core ◽  
Ballistic Performance ◽  
Damage Area ◽  
Honeycomb Sandwich ◽  
Aluminum Honeycomb ◽  
Honeycomb Sandwich Structure

This study investigates damage mechanisms and deformation of honeycomb sandwich structures reinforced by functionally graded face plates under ballistic impact. The honeycomb sandwich structure consists of two identical functionally graded face sheets, having different material compositions through the thickness, and an aluminum honeycomb core. The functionally graded face sheets consist of ceramic (SiC) and aluminum (Al 6061) phases. The through-thickness mechanical properties of face sheets are assumed to vary according to a power-law. The locally effective material properties are evaluated using the Mori–Tanaka scheme. The effect of material composition of functionally graded face sheets on the ballistic performance of honeycomb sandwich structures was investigated using the finite element method and the penetration and perforation threshold energy values on ballistic performance and ballistic limit of the sandwich structures are determined. The contribution of the honeycomb core on the ballistic performance of the sandwich structure was evaluated by comparing with spaced plates (without honeycomb core) in terms of the residual velocity, kinetic energy, and damage area.

Numerical and experimental investigation for enhancing the energy absorption capacity of the novel three-dimensional printed sandwich structures

2021 ◽  
pp. 146442072199749
Author(s):  
H Geramizadeh ◽  
S Dariushi ◽  
S Jedari Salami
Keyword(s):  
Energy Absorption ◽  
Sandwich Structures ◽  
Three Dimensional ◽  
Absorption Capacity ◽  
The Novel ◽  
Energy Absorption Capacity ◽  
Fused Deposition ◽  
Honeycomb Sandwich ◽  
Out Of Plane ◽  
Vertical Walls

The current study focuses on designing the optimal three-dimensional printed sandwich structures. The main goal is to improve the energy absorption capacity of the out-of-plane honeycomb sandwich beam. The novel Beta VI and Alpha VI were designed in order to achieve this aim. In the Beta VI, the connecting curves (splines) were used instead of the four diagonal walls, while the two vertical walls remained unchanged. The Alpha VI is a step forward on the Beta VI, which was promoted by filleting all angles among the vertical walls, created arcs, and face sheets. The two offered sandwich structures have not hitherto been provided in the literature. All models were designed and simulated by the CATIA and ABAQUS, respectively. The three-dimensional printer fabricated the samples by fused deposition modeling technique. The material properties were determined under tensile, compression, and three-point bending tests. The results are carried out by two methods based on experimental tests and finite element analyses that confirmed each other. The achievements provide novel insights into the determination of the adequate number of unit cells and demonstrate the energy absorption capacity of the Beta VI and Alpha VI are 23.7% and 53.9%, respectively, higher than the out-of-plane honeycomb sandwich structures.

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