Nonlinear dynamics of viscoelastic flexible structural systems by finite element method (original) (raw)
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European Journal of Computational Mechanics
Suspension systems in running vehicles keep the occupants comfortable and isolated from road noise, disturbances, and vibrations and consequently prevent the vehicle from damage and wearing. To attain comfortable and vibration isolation conditions, both material flexibility and damping should be considered in the considered suspension model. This paper presents an incremental finite element model to study and analyze the dynamic behavior of double wishbone suspension systems considering both material flexibility and damping effects. The flexibility of the suspension links are modeled with plane frame element based on Timoshenko beam hypothesis (TBH). On the other hand, the flexibility of joints connecting the suspension links together and with the vehicle chassis is modeled with the revolute joint element. To incorporate the damping effect, viscoelastic, viscous and proportional damping are considered. An incremental viscoelastic constitutive relations, suitable for finite element i...
Finite Element Analysis of Double Wishbone Vehicle Suspension System
Egyptian Journal for Engineering Sciences and Technology, 2019
Suspension systems play an important role in vehicles. These systems provide passenger comfort and vibration isolation from road bumps. Thus an efficient finite element model is required to study and analyze the dynamic response of these suspension systems. This paper presents a finite element model to analyze the dynamic response of double wishbone vehicle suspension system taking into consideration both links and joints flexibilities. Links are modeled using plane frame element based on Timoshenko beam theory (TBT) kinematic relations. On the other hand, the revolute joint element, developed in ANSYS, is adopted to model joints flexibility.Both internal viscoelastic and external viscous as well as the modal proportional damping models are adopted to simulate the damping effect. The resulting dynamic finite element equations of motion are solved using Newmark numerical technique. The proposed numerical methodology is checked by comparing the obtained results with the developed anal...
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IOP Conference Series: Materials Science and Engineering, 2017
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DYNAMIC ANALYSIS OF DOUBLE WISHBONE SUSPENSION
İZMİR ACKNOWLEDGEMENTS I would like to take this opportunity to express my gratitude to my supervisor Assoc. Prof. Dr. Bülent YARDIMOĞLU for his constant guidance and encouragement during the past one year. He always appreciates whatever little progress I have achieved, and continuously gives me much inspiration by sharing his precious knowledge and experience. I would also like to thank my husband for his supports, emotionally and financially. He is always here for me whenever I need his help.
Structural Analysis of Double-Wishbone Suspension System
International Journal for Research in Applied Science & Engineering Technology (IJRASET), 2021
A suspension system is a crucial part of the vehicle system which assists in handling the vehicle and safety of the occupants. From leaf spring type suspension to multi-link suspension and modern adaptive suspension systems, different modifications and researches are practiced to enhance dynamic characteristics of suspension optimizing drivability and ride comfort. The presented study focuses on the analysis of double wishbone suspension system. The components used and working of this suspension are also explained as well as the numerical calculation for creation of the spring is presented. The Finite Element Analysis (FEA) is carried out using Simscale software. The suspension is analyzed through static analysis and results show acceptable values.
Modeling of Vertical Dynamic Vibration Characteristics on Vehicles Suspension System
IOP Conference Series: Materials Science and Engineering
Vibrations often interfere with driving comfort for riders and passengers. Variations in loads, especially for four-wheeled vehicles, bumps, hollow road surfaces, and other forms of road damage will greatly affect the vehicle suspension work system. This research aims to (1) further test the effect of vertical dynamic load of the vehicle and change the dimension of resistance on the road surface, (2) the contribution of spring and shock absorber to the load fluctuation of the vehicle. Experimentally these load fluctuations are replaced by pneumatic actuator forces of varying magnitude based on the regulatory pressure of the regulator. The deviations generated by the varying load work are measured by placing a proximity sensor along the spring movement. The vertical dynamic load transformation up to the road surface is measured using a "Load cell" mounted under the wheels of the vehicle. Characteristics of vertical dynamic vibration occurring due to several dimensional barriers, U (cm) obtained using mathematical modeling method with 2 DOF suspension system transfer function. The results showed a condition on the body and wheels of vehicles experienced a brief overshot for 0.14 seconds with deviation of 0.178 m. From the graph shows that the rate of deviation that occurs is large enough that Y2d = 1.03 m / s caused by a sudden shock that occurred on the wheels of the vehicle. This condition does not last long that is only duration t = 0.22 s, because the contribution of springs and shock absorbers that can absorb vibration is 25% to the vibrations caused by the vertical load of the body and the axis of the vehicle.
Advances in Mechanical Engineering, 2016
Passive shock absorbers are designed for standard load condition. These give better vibration isolation performance only for the standard load condition. However, if the sprung mass is lesser than the standard mass, comfort and road holding ability is affected. It is demonstrated that sprung mass acceleration increases by 50%, when the vehicle mass varies by 100 kg. In order to obtain consistent damping performance from the shock absorber, it is essential to vary its stiffness and damping properties. In this article, a variable stiffness system is presented, which comprises of two helical springs and a variable fluid damper. Fluid damper intensity is changed in four discrete levels to achieve variable stiffness of the prototype. Numerical simulations have been performed with MATLAB Simscape and Simulink which have been with experimentation on a prototype. Furthermore, the numerical model of the prototype is used in design of real size shock absorber with variable stiffness and dampi...
Dynamical Analysis of an Off-Road Vehicle Suspension
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A theoretical analysis of a new proposed variable stiffness model of the suspension system is studied to improve the traditional suspension system. The fundamental idea of system centered on variable stiffness mechanism by added subsystem to suspension system depended on control rotating arm balancing the force between sides, it consists of a vertical control strut. The variation of the load transfer by rotate arm has spring and damper at another side of it where the point of rotation is supplement the body of car by sup system as vertical support. The investigations of the new variable by addition stiffness to the suspension system for reaches improved performance better than the variable stiffness systems for equivalent or traditional. The expending principles to described the performance of the characteristic behavior of system are fewer car body acceleration to ride comfort and lower suspension and tire deflection for road holding considered.
Design of Automotive Torsion Beam Suspension Using Lumped-Compliance Linkage Models
Design Engineering and Computers and Information in Engineering, Parts A and B, 2006
This paper presents a new method for efficiently and accurately modeling the elasto-kinematic behaviors of torsion beam suspension systems and of other similar classes of mechanical systems, and a design method utilizing the models. The torsion beam is represented as a linkage of lumped mass joined by nonlinear springs, bending and torsion, whose stiffness are identified via off-line computational experiments using nonlinear finite element simulations. A number of such computer experiments are conducted off-line for representative dimensions of torsion beams, and the results are stored in surrogate response models. During design iterations, these surrogate response models are utilized to automatically construct a lumped-compliance linkage model of a torsion beam and integrate it into a multi-body suspension system model that can be simulated using commercial software. Comparison with a nonlinear finite element analysis demonstrates much improved accuracy of the proposed model over commercial flexible multi-body simulation software, with comparable computational speed. Finally, an example is presented on the multi-objective optimization of the cross section of the torsion beam using the developed surrogate response models.