Mathematical modeling of elastoplastic deformation of tubular energy-absorbing elements under static and impact loading

2020 ◽  
pp. 78-82
Author(s):  
A.Р. Evdokimov ◽  
A.N. Gromyiko ◽  
A.A. Mironov
Keyword(s):  
Mathematical Modeling ◽  
Impact Loading ◽  
Elastoplastic Deformation ◽  
Shock Absorber ◽  
Analytical Models ◽  
Dynamic Impact ◽  
Shock Absorbers ◽  
Energy Absorbing ◽  
Absorbing Elements

Analytical models of static and dynamic impact elastoplastic deformation of tubular energy-absorbing elements constituting a tubular plastic shock absorber are proposed. The developed models can be used for the calculation and design of these shock absorbers. Keywords static and dynamic elastoplastic deformation, mathematical modeling, tubular energy-absorbing element, tubular plastic shock absorber, impact loading. [email protected]

Mathematical Modeling of a New Improved Design of a Rail Carriage Suspension System for the Wagons Used in Zimbabwe

2009 ◽  
Vol 62-64 ◽  
pp. 645-654 ◽  
Author(s):  
C. Mbohwa ◽  
J. Agwa-Ejon ◽  
C. Murasiki
Keyword(s):  
Mathematical Modeling ◽  
Shock Absorber ◽  
Ride Comfort ◽  
Suspension System ◽  
Human Comfort ◽  
Research Issues ◽  
Vibration Transmission ◽  
Shock Absorbers ◽  
Improved Design ◽  
Dynamic Attributes

This paper discusses the mathematical modeling of a new improved design of the carriage bogie suspension system with emphasis on design for human comfort. The research mainly covered the shock absorbers with the aim of improving ride comfort at higher speeds. The paper focuses on how to reduce vibration transmission to the carriage while designing a railway bogie suspension damping system that is easier to maintain but does not compromise on quality with particular interest in dynamic attributes of the shock absorber. The principal research issues are introduced and looked at in the modeling and the results so obtained are used to calculate the relative transmissibility in the motion of the carriage.

scholarly journals Application of an Additive Manufactured Hybrid Metal/Composite Shock Absorber Panel to a Military Seat Ejection System

2021 ◽  
Vol 11 (14) ◽  
pp. 6473
Author(s):  
Valerio Acanfora ◽  
Chiara Corvino ◽  
Salvatore Saputo ◽  
Andrea Sellitto ◽  
Aniello Riccio
Keyword(s):  
Numerical Simulation ◽  
Additive Manufacturing ◽  
Total Mass ◽  
Shock Absorber ◽  
Metal Composite ◽  
Plastic Deformations ◽  
Shock Absorbers ◽  
Numerical Assessment ◽  
Lattice Core ◽  
Ejection Phase

In this work, a preliminary numerical assessment on the application of an additive manufactured hybrid metal/composite shock absorber panels to a military seat ejection system, has been carried out. The innovative character of the shock absorber concept investigated is that the absorbing system has a thickness of only 6 mm and is composed of a pyramid-shaped lattice core that, due to its small size, can only be achieved by additive manufacturing. The mechanical behaviour of these shock absorber panels has been examined by measuring their ability to absorb and dissipate the energy generated during the ejection phase into plastic deformations, thus reducing the loads acting on pilots. In this paper the effectiveness of a system composed of five hybrid shock absorbers, with very thin thickness in order to be easily integrated between the seat and the aircraft floor, has been numerically studied by assessing their ability to absorb the energy generated during the primary ejection phase. To accomplish this, a numerical simulation of the explosion has been performed and the energy absorbed by the shock-absorbing mechanism has been assessed. The performed analysis demonstrated that the panels can absorb more than 60% of the energy generated during the explosion event while increasing the total mass of the pilot-seat system by just 0.8%.

Double Adjustable Shock Absorbers Utilizing Electrorheological and Magnetorheological Fluids

2000 ◽  
Author(s):  
Jason E. Lindler ◽  
Norman M. Wereley
Keyword(s):  
Shock Absorber ◽  
Force Measurements ◽  
Damping Force ◽  
University Of Maryland ◽  
Shock Absorbers ◽  
Piston Head ◽  
Performance Requirements ◽  
Velocity Response ◽  
The University ◽  
Yield Force

Abstract Double adjustable shock absorbers allow for independent adjustment of the yield force and post-yield damping in the force versus velocity response. To emulate the performance of a conventional double adjustable shock absorber, an electrorheological (ER) and magnetorheological (MR) automotive shock absorber were designed and fabricated at the University of Maryland. For the ER shock absorber, an applied electric field between two tubular electrodes, located in the piston head, increases the force required for a given piston rod velocity. For the MR shock absorber, an applied magnetic field between the core and flux return increases the force required for a given piston rod velocity. For each shock absorber, two different shaped gaps meet the controllable performance requirements of a double adjustable shock absorber. A uniform gap allows for control of the yield force of the shock absorber, while a non-uniform gap allows for control of the post-yield damping. Force measurements from sinusoidal displacement cycles, recorded on a mechanical damper dynamometer, validate the performance of uniform and non-uniform gaps for adjustment of the yield force and post-yield damping, respectively.

On-Field Measurements of the Dissipated Vibrational Power of an SUV Car Traditional Viscous Shock Absorber

2018 ◽  
Author(s):  
Mohamed A. A. Abdelkareem ◽  
Lin Xu ◽  
Mohamed Kamal Ahmed Ali ◽  
Mohamed A. Hassan ◽  
Ahmed Elagouz ◽  
...  
Keyword(s):  
Shock Absorber ◽  
Average Power ◽  
Field Measurements ◽  
Velocity Range ◽  
Suspension Systems ◽  
Shock Absorbers ◽  
Road Section ◽  
Speed Range ◽  
System Body ◽  
Acceleration Signals

The current paper provides some on-field measurements regarding the quantification of the dissipated power during the damping process of a traditional viscous shock absorber. In this regard, the HAVAL H8 SUV was driven for several trips on the Nanhu campus arena considering a velocity range of 20–50 km/h. Furthermore, two species of campus road sections were selected during the fabricated tests; straight road section with and without a speed bump. The acceleration signals of the rear-right suspension system (body and wheel) were acquired as the average power dissipation trend could be calculated from the relative suspension velocity. The findings of this investigation indicate that the average dissipated power of a traditional shock absorber can be in a range of 10–90 W for a speed range of 20–50 km/h driving on a campus road section free of speed bumps. Whilst, for another road segment with one speed bump, the shock absorber dissipated a kinetic energy between 40–140 W for a velocity range of 20–50 km/h. Suggesting that an average overall dissipated power of 160–560 W is available by means of the traditional shock absorbers. The results are of strategic interest for the researchers and vehicle manufacturers for further considerations in terms of regenerative suspension systems where a part of this energy could be harvested instead of being wholly dissipated.

Dynamic Impact Testing of Polyurethane Energy Absorbing (EA) Foams

1994 ◽  
Author(s):  
David F. Sounik ◽  
Dennis W. McCullough ◽  
John L. Clemons ◽  
John L. Liddle
Keyword(s):  
Impact Testing ◽  
Dynamic Impact ◽  
Energy Absorbing

Modelling the Dynamic Behaviour of A Motorcycle Damper

1995 ◽  
Vol 209 (4) ◽  
pp. 249-262 ◽  
Author(s):  
A L Audenino ◽  
G Belingardi
Keyword(s):  
Shock Absorber ◽  
Dynamic Behaviour ◽  
Fluid Dynamic ◽  
Critical Factor ◽  
Physical Models ◽  
Vehicle Suspension ◽  
Shock Absorbers ◽  
Internal Fluid ◽  
Output Force ◽  
Dependent Behaviour

Within the context of vehicle suspension component characterization, that of shock absorbers is one of the more difficult to achieve, yet it is a very critical factor in the prediction of vehicle dynamic behaviour. Strongly non-linear output force functions are always linked to a frequency-dependent behaviour. Using the internal fluid-dynamic phenomenon with respect to a motorcycle shock absorber, different physical models of increasing complexity are presented: using these models it is possible to evaluate the importance of different factors, for example oil compressibility or oil inertia. Comparisons with experimental data confirm the validity of these models

Effect of Material Composition on Impact Energy Absorbing Capability of Composite Laminates

2016 ◽  
Vol 715 ◽  
pp. 147-152
Author(s):  
Ryota Haruna ◽  
Takayuki Kusaka ◽  
Ryota Tanegashima ◽  
Junpei Takahashi
Keyword(s):  
Impact Loading ◽  
Composite Laminates ◽  
Fiber Type ◽  
Material Composition ◽  
Control Technique ◽  
Dynamic Stress Field ◽  
Split Hopkinson ◽  
Split Hopkinson Pressure Bars ◽  
Crushing Behavior ◽  
Energy Absorbing

A novel experimental method was proposed for characterizing the energy absorbing capability of composite materials during the progressive crushing process under impact loading. A split Hopkinson pressure bars system was employed to carry out the progressive crushing tests under impact loading. The stress wave control technique was used to avoid the inhomogeneity of dynamic stress field in the specimen. The progressive crushing behavior was successfully achieved by using a coupon specimen and anti-buckling fixtures. With increasing strain rate, the absorbed energy during the crushing process slightly decreased, whereas the volume of the damaged part clearly increased regardless of material type. Consequently, the energy absorbing capability decreased with increasing loading rate. The effects of material composition, such as fiber type, matrix type and fabric pattern, on energy absorbing capability were also investigated by using the proposed method.

scholarly journals Failure characteristics of the isolated distal radius in response to dynamic impact loading

2011 ◽  
Vol 30 (6) ◽  
pp. 885-892 ◽  
Author(s):  
Timothy A. Burkhart ◽  
David M. Andrews ◽  
Cynthia E. Dunning
Keyword(s):  
Distal Radius ◽  
Impact Loading ◽  
Dynamic Impact ◽  
Failure Characteristics ◽  
Dynamic Impact Loading

Electromagnetic Shock Absorbers for Automotive Suspensions: Electromechanical Design

2006 ◽  
Author(s):  
Nicola Amati ◽  
Aldo Canova ◽  
Fabio Cavalli ◽  
Stefano Carabelli ◽  
Andrea Festini ◽  
...  
Keyword(s):  
Shock Absorber ◽  
Dynamic Performance ◽  
Integrated Design ◽  
Design Procedure ◽  
Resistive Load ◽  
Added Resistance ◽  
Damping Force ◽  
Quarter Car Model ◽  
Car Model ◽  
Shock Absorbers

This article illustrates the modeling and design of electromechanical shock absorbers for automotive applications. Relative to the commonly used hydraulic shock absorbers, electromechanical ones are based on the use of linear or rotative electric motors. If electric motor is of the DC-brushless type, the shock absorber can be devised by shunting its electric terminals with a resistive load. The damping force can be modified by acting on the added resistance. An integrated design procedure of the electrical and mechanical parameters is presented in the article. The dynamic performance that can be obtained by a vehicle with electromechanical dampers is verified on a quarter car model.

Dynamic Impact Measurements on Crossings, in Free Floating and In-Situ Conditions

2014 ◽  
Author(s):  
M. A. Boogaard ◽  
A. L. Schwab ◽  
Z. Li
Keyword(s):  
Finite Element ◽  
Condition Monitoring ◽  
Impact Loading ◽  
Dynamic Behaviour ◽  
Element Model ◽  
Mode Shapes ◽  
Dynamic Impact ◽  
In Situ Test ◽  
In Situ Conditions

As vibration based condition monitoring requires a good understanding of the dynamic behaviour of the structure, a good model is needed. At the TU Delft a train borne monitoring system is being developed which currently focusses on crossings. Crossings are prone to very fast degradation due to impact loading. In this paper a finite element model of a free floating frog is presented and validated up to a 100 Hz using dynamic impact measurements. The mode shapes of the free floating frog are then also compared to some preliminary results from an in-situ test. This comparison shows that the in-situ frequencies can be up to twice the free floating frequency.

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