scholarly journals Crashworthiness Analysis of Octagonal-Inner Double Tube with different thickness under Off-Axis Oblique Load

2020 ◽  
Vol 14 ◽  
Keyword(s):  
Impact Load ◽  
Rigid Wall ◽  
Oblique Impact ◽  
Element Analysis ◽  
Frontal Crash ◽  
Moving Wall ◽  
Oblique Loading ◽  
Crashworthiness Analysis ◽  
Oblique Load ◽  
Different Thickness

The crash tube is one of the important parts to reduce the effects of accidents. The design of crash tube only watches the frontal crash, but oblique crash might affect the passengers. Besides, Lack of oblique-loading researches in crashworthiness becomes causes to analyze crash tubes more. This paper aims to study crashworthiness performance of octagonal-inner double tubes under off-axis oblique impact load (0°, 10°, 20°, and 30°). The tubes have been connected with two walls, top wall as moving wall and a bottom wall as rigid wall underl different load angles. The tubes were made from Aluminum Alloy and consisted of a circular-outer tube and an octagonal-inner tube. The crashworthiness parameters of absorption of specific energy (SEA), maximum collapse force (Fmax) and efficiency of crush force (CFE) were obtained for all the structures. In order to get the value of parameters, the method of finite element analysis was used. The effects of different thickness of 1 mm, 2 mm, 3 mm and 4 mm and various oblique were studied. Based on numerical results, structures of 4 mm thickness were the greatest SEA of 26.39 kJ/kg among other thickness of structures. In addition, the value of energy absorption for tubes obliquely loaded decreased for all the size of thickness structures. Finally, this structure can be considered as crash box of vehicle in future

Impact Load Buffering Method Based on Stress Wave Attenuation Principle

2019 ◽  
Vol 11 (02) ◽  
pp. 1950019 ◽  
Author(s):  
Lin Gan ◽  
He Zhang ◽  
Cheng Zhou ◽  
Lin Liu
Keyword(s):  
Stress Wave ◽  
Wave Attenuation ◽  
Impact Load ◽  
Dynamics Simulation ◽  
Scanning System ◽  
Isolation Method ◽  
Element Analysis ◽  
System A ◽  
High Emission ◽  
The Impact

Rotating scanning motor is the important component of synchronous scanning laser fuze. High emission overload environment in the conventional ammunition has a serious impact on the reliability of the motor. Based on the theory that the buffer pad can attenuate the impact stress wave, a new motor buffering Isolation Method is proposed. The dynamical model of the new buffering isolation structure is established by ANSYS infinite element analysis software to do the nonlinear impact dynamics simulation of rotating scanning motor. The effectiveness of Buffering Isolation using different materials is comparatively analyzed. Finally, the Macht hammer impact experiment is done, the results show that in the experience of the 70,000[Formula: see text]g impact acceleration, the new buffering Isolation method can reduce the impact load about 15 times, which can effectively alleviate the plastic deformation of rotational scanning motor and improve the reliability of synchronization scanning system. A new method and theoretical basis of anti-high overload research for Laser Fuze is presented.

Bond Thickness Effects upon Dynamic Behaviour in Adhesive Joints

2010 ◽  
Vol 97-101 ◽  
pp. 3920-3923 ◽  
Author(s):  
Xiao Cong He
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Dynamic Behaviour ◽  
Adhesive Layer ◽  
Adhesive Joints ◽  
Response Functions ◽  
Frequency Range ◽  
Element Analysis ◽  
Cantilevered Beam ◽  
Different Thickness

The influence of adhesive layer thickness on the dynamic behaviour of the single-lap adhesive joints is investigated in this paper. The ABAQUS finite element analysis (FEA) software was used to predict the frequency response functions (FRFs) of the single-lap adhesive joints of different thickness of the adhesive layer. As a reference, the FRFs of a cantilevered beam without joint were investigated as well. It is clear that the FRFs of the four beams are close to each other within the frequency range 0~1000 Hz. It is also found that the composite damping of the single-lap adhesive joint increases as the thickness of the adhesive layer increases.

Dynamic Loading Approach for Structural Evaluation of Ultra Large Container Carriers

2005 ◽  
Author(s):  
Bill Shi ◽  
Donald Liu ◽  
Christopher Wiernicki
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Dynamic Loading ◽  
Impact Load ◽  
Failure Mechanisms ◽  
Direct Calculation ◽  
Element Analysis ◽  
Design Philosophy ◽  
Non Linear ◽  
Large Container

The emerging global economic needs are driving the designs for the next generation of ocean going vessels. Current ultra-large container carrier (10,000 TEU plus) designs are considerably larger and more complex than any currently in service. Proper and rational classification assessment requires that first principles based direct calculation methods be used to augment the standard classification review. The design philosophy behind the ABS Dynamic Loading Approach enables comprehensive identification of potential failure mechanisms. The scope of the necessary engineering assessment encompass full-ship finite element analysis under non-linear sea loads, spectral fatigue analysis, finite element lashing analysis, free and forced vibration analysis, and transient and impact load analysis. This paper describes key aspects of the DLA design philosophy such as non-linear sea loads, load combinations, various applications derived from full-ship finite element analysis. Several examples are given to highlight some critical failure mechanisms to be considered for ultra-large container carriers.

A Study on Durability Enhancement of Band Brake for Mooring Winch

2011 ◽  
Vol 201-203 ◽  
pp. 314-317
Author(s):  
Dong Seop Han ◽  
Geun Jo Han ◽  
Dong Hwan Choi
Keyword(s):  
Brake System ◽  
Analytic Model ◽  
Uniform Thickness ◽  
Element Analysis ◽  
Brake Shoe ◽  
The Finite Element Analysis ◽  
Brake Lining ◽  
Different Thickness ◽  
Ansys Workbench ◽  
Excessive Stress

The brake system is very important part of the machine working. The mooring winch brake holds the ship on the harbor. But sometimes it appeared the excessive stress and brake lining would be broken. So it is necessary to change the shape of brake system with improve the durability of brake band. In this research, three models, such as a single brake shoe with a uniform thickness, a dual brake shoe with a uniform thickness, and a dual brake shoe with different thickness, are adopted as analytic model. In order to evaluate the strength of band brake according to the shape of brake shoe, the finite element analysis for three models is carried out by using ANSYS Workbench.

Effect of Strain Rate on the Simulation of MEMS Safety and Arming Device

2014 ◽  
Vol 609-610 ◽  
pp. 849-855
Author(s):  
Wen Rui Ma ◽  
Guang He
Keyword(s):  
Finite Element Analysis ◽  
Strain Rate ◽  
Impact Load ◽  
Simulation Models ◽  
Strain Rate Effect ◽  
Rate Effect ◽  
Experimental Results ◽  
Analysis Software ◽  
Element Analysis ◽  
Simulation Results

Under launch impact load, LIGA nickel that manufacturing MEMS fuze safety and arming (S&A) device will have obvious strain rate effect. By using finite element analysis software ANSYS/LS-DYNA, simulation models of a small-caliber ammunition MEMS fuze setback S&A device with strain rate effect and without strain rate effect were respectively established. The results of the two simulation modules were quite different. Comparisons between experimental results and simulation results show that simulation results considering strain rate effect agree well with experimental results, which proves strain rate effect should not be ignored in the simulation of MEMS S&A device.

Prehistoric Effect of the Stamping Process on the Crash Analysis of an Automobile under Frontal Impact

2013 ◽  
Vol 711 ◽  
pp. 149-154 ◽  
Author(s):  
Se Ho Kim
Keyword(s):  
Impact Load ◽  
Crash Analysis ◽  
Frontal Impact ◽  
Vehicle Model ◽  
Side Member ◽  
Frontal Crash ◽  
Full Vehicle ◽  
Load Carrying ◽  
Crash Characteristics ◽  
The Impact

In this paper, a frontal crash analysis is carried out with a full vehicle model in order to investigate the influence of stamping effects of auto-body members on the crash characteristics of the vehicle. Stamping effects are considered for load carrying members such as the front side member and the rear lower. From the analysis result considering stamping effects, it is conformed that stamping history has to be considered for longitudinal members simultaneously that transfer the impact load under the frontal impact. Comparison of simulation result with experimental one also shows that the prediction accuracy of the crash analysis is remarkably improved.

scholarly journals On the Role and Effects of Uncertainties in Cardiovascular in silico Analyses

2021 ◽  
Vol 3 ◽  
Author(s):  
Simona Celi ◽  
Emanuele Vignali ◽  
Katia Capellini ◽  
Emanuele Gasparotti
Keyword(s):  
Computational Analysis ◽  
Rigid Wall ◽  
Patient Specific ◽  
Computational Techniques ◽  
Error Sources ◽  
Moving Wall ◽  
Cardiovascular Hemodynamics ◽  
Computational Fluid Dynamics Cfd ◽  
Flow Pressure ◽  
Different Levels

The assessment of cardiovascular hemodynamics with computational techniques is establishing its fundamental contribution within the world of modern clinics. Great research interest was focused on the aortic vessel. The study of aortic flow, pressure, and stresses is at the basis of the understanding of complex pathologies such as aneurysms. Nevertheless, the computational approaches are still affected by sources of errors and uncertainties. These phenomena occur at different levels of the computational analysis, and they also strongly depend on the type of approach adopted. With the current study, the effect of error sources was characterized for an aortic case. In particular, the geometry of a patient-specific aorta structure was segmented at different phases of a cardiac cycle to be adopted in a computational analysis. Different levels of surface smoothing were imposed to define their influence on the numerical results. After this, three different simulation methods were imposed on the same geometry: a rigid wall computational fluid dynamics (CFD), a moving-wall CFD based on radial basis functions (RBF) CFD, and a fluid-structure interaction (FSI) simulation. The differences of the implemented methods were defined in terms of wall shear stress (WSS) analysis. In particular, for all the cases reported, the systolic WSS and the time-averaged WSS (TAWSS) were defined.

Effective in-plane elastic properties of honeycomb-polymer composites

2021 ◽  
pp. 002199832110547
Author(s):  
Carson Squibb ◽  
Michael Philen
Keyword(s):  
Polymer Composites ◽  
Elastic Properties ◽  
Effective Properties ◽  
Rigid Wall ◽  
Cell Geometry ◽  
Element Analysis ◽  
Parametric Studies ◽  
Honeycomb Cell ◽  
Infill Material ◽  
Analytic Models

Honeycomb composites are now common materials in applications where high specific stiffness is required. Previous research has found that honeycombs with polymer infills in their cells, here referred to as honeycomb-polymer composites (HPCs), exhibit effective stiffnesses greater than the honeycomb or polymer alone. Currently, the state of analytic models for predicting the elastic properties of these composites is limited, and further research is needed to better characterize the behavior of these materials. In this research, a nonlinear finite element analysis was employed to perfor2m parametric studies of a filled honeycomb unit cell with isotropic wall and infill materials. A rigid wall model was created as an upper bound on the deformable wall model’s performance, and an empty honeycomb model was employed to better understand the mechanisms of stiffness amplification. Parametric studies were completed for infill material properties and cell geometry, with the effective Young’s modulus studied in two in-plane material directions. The mechanisms by which the stiffness amplification occurs are studied, and comparisons to existing analytic models are made. It has been observed that both the volume change within the honeycomb cell under deformation and the mismatch in Poisson’s ratios between the honeycomb and infill influence the effective properties. Stiffness amplifications of over 4000 have been observed, with auxetic behavior achieved by tailoring of the HPC geometry. Additionally, the effect of large effective strains up to 10% is explored, where the cell geometry changes significantly. This research provides an important step toward understanding the design space and benefits of HPCs.

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