Circular Contact of Incompressible, Nonlinear-Elastic Bodies

2009 ◽  
Author(s):  
Emanuel Diaconescu ◽  
Marilena Glovnea ◽  
Filip Ciutac
Keyword(s):  
Nonlinear Elasticity ◽  
Simple Approach ◽  
Experimental Results ◽  
Contact Modeling ◽  
Elastic Bodies ◽  
Nonlinear Elastic ◽  
Theory And Experiments ◽  
Circular Contact ◽  
Good Agreement

Contact modeling of rubber bodies is based either on viscoelasticity, nonlinear elasticity or adhesion. This paper advances a simple approach to the analysis of the contacts involving incompressible, nonlinear elastic bodies and reports experimental results on rubber to justify this approach. A good agreement is found between theory and experiments.

Finite deformation of flexible composites

1990 ◽  
Vol 429 (1877) ◽  
pp. 569-586 ◽  
Keyword(s):  
Finite Deformation ◽  
Constitutive Relations ◽  
Elastic Behaviour ◽  
Flexible Composites ◽  
Lagrangian Strain ◽  
Strain Components ◽  
Nonlinear Elastic ◽  
Fourth Order Polynomial ◽  
Theory And Experiments ◽  
Good Agreement

This paper examines the nonlinear elastic behaviour of flexible composites under finite deformation. The constitutive relations have been derived based on a strain-energy density which, in a fourth-order polynomial form, is assumed to be a function of the lagrangian strain components referring to the initial principal material coordinates. The constitutive equations thus obtained are verified by the following experiments: (1) off-axis tension and simple shear for unidirectional composites, and (2) uniaxial tension for flexible composites with wavy fibres. Good agreement has been found between the theory and experiments.

The Role of Elastic Tangential Compliance in Oblique Impact

1981 ◽  
Vol 103 (1) ◽  
pp. 74-80 ◽  
Author(s):  
N. Maw ◽  
J. R. Barber ◽  
J. N. Fawcett
Keyword(s):  
Coulomb Friction ◽  
Oblique Impact ◽  
Angle Of Incidence ◽  
Elastic Bodies ◽  
Moving Body ◽  
Before And After ◽  
Local Angle ◽  
Circular Contact ◽  
Good Agreement

An extension of the Hertz theory of impact to the oblique impact of elastic bodies with circular contact is outlined. The tangential compliance of the contact surface under the action of Coulomb friction is shown to have a significant effect on the rebound angles, if the local angle of incidence does not greatly exceed the angle of friction. Experiments are described in which the trajectory of a moving body is measured before and after impact with a fixed block of similar material. Results obtained using both steel and rubber show good agreement with the theoretical values.

Mechanical Modeling of Fabrics in Bending

2004 ◽  
Vol 71 (1) ◽  
pp. 32-40 ◽  
Author(s):  
T. J. Lahey ◽  
G. R. Heppler
Keyword(s):  
Nonlinear Elasticity ◽  
Evaluation System ◽  
Coulomb Friction ◽  
Experimental Results ◽  
Hysteretic Behavior ◽  
Elastic Behavior ◽  
Loading Conditions ◽  
Mechanical Modeling ◽  
Bending Tests ◽  
Nonlinear Elastic

A fabric bending model that includes contributions from nonlinear elasticity, and viscous and Coulomb friction with hysteretic effects is presented. The model allows the recovery of the loading, unloading and hysteresis behaviors observed in the Kawabata evaluation system (KES) bending tests and provides the ability to simulate a continuum of property curves and to extrapolate to loading conditions not covered in the KES regimen. Model results are compared to experimental results. It is found that hysteretic behavior is observed due to friction between the yarns, and that nonlinear elastic behavior arises from jamming of the yarns and their subsequent compression.

Characterization of the torsional vibration behavior of circular and rectangular cross-sectional arc springs: Theory and experiments

2021 ◽  
Vol 63 (2) ◽  
pp. 113-118
Author(s):  
Samet Fidanciogullari ◽  
Ahmet Yildiz
Keyword(s):  
Torsional Vibration ◽  
Experimental Tests ◽  
Experimental Results ◽  
Experimental Characterization ◽  
Cross Sectional ◽  
Vibration Behavior ◽  
The Masses ◽  
Theory And Experiments ◽  
Good Agreement

Abstract This paper is about the theoretical and experimental characterizations of the torsional vibration behavior of circular and rectangular cross-sectional arc springs. Firstly, the dynamic behaviors of arc springs with different cross-sectional wire profiles designed for a dual mass flywheel are modeled by mathematical formulations. After that, experimental tests are performed to verify these models and it is observed that the stiffness characterizations are in good agreement with experimental results. Lastly, the masses of two different arc springs are compared by regarding the same vibration stiffness criteria and it is demonstrated that the rectangular wire provides an arc spring with a 9.44 vol.-% lighter structure. Thus, the outcomes of this paper can be good references for the manufacturer about the numerical and experimental characterization of dual mass flywheel springs, especially for rectangular wire arc springs.

Inducing Frictional Force to Enhance the Transient Response in Beams

2019 ◽  
Vol 22 (2) ◽  
pp. 88-93
Author(s):  
Hamed Khanger Mina ◽  
Waleed K. Al-Ashtrai
Keyword(s):  
Numerical Analysis ◽  
Transient Response ◽  
Frictional Force ◽  
Damping Ratio ◽  
Experimental Results ◽  
Damping Capacity ◽  
Tightening Force ◽  
Contact Areas ◽  
Good Agreement ◽  
Ansys Workbench

This paper studies the effect of contact areas on the transient response of mechanical structures. Precisely, it investigates replacing the ordinary beam of a structure by two beams of half the thickness, which are joined by bolts. The response of these beams is controlled by adjusting the tightening of the connecting bolts and hence changing the magnitude of the induced frictional force between the two beams which affect the beams damping capacity. A cantilever of two beams joined together by bolts has been investigated numerically and experimentally. The numerical analysis was performed using ANSYS-Workbench version 17.2. A good agreement between the numerical and experimental results has been obtained. In general, results showed that the two beams vibrate independently when the bolts were loosed and the structure stiffness is about 20 N/m and the damping ratio is about 0.008. With increasing the bolts tightening, the stiffness and the damping ratio of the structure were also increased till they reach their maximum values when the tightening force equals to 8330 N, where the structure now has stiffness equals to 88 N/m and the damping ratio is about 0.062. Beyond this force value, increasing the bolts tightening has no effect on stiffness of the structure while the damping ratio is decreased until it returned to 0.008 when the bolts tightening becomes immense and the beams behave as one beam of double thickness.

PHOTOINDUCED NONLINEAR OCTUPOLAR POLARIZATION: TRANSIENT AND PERMANENT REGIMES

1996 ◽  
Vol 05 (04) ◽  
pp. 653-670 ◽  
Author(s):  
CÉLINE FIORINI ◽  
JEAN-MICHEL NUNZI ◽  
FABRICE CHARRA ◽  
IFOR D.W. SAMUEL ◽  
JOSEPH ZYSS
Keyword(s):  
Theoretical Analysis ◽  
Second Harmonic ◽  
Experimental Results ◽  
Polar Field ◽  
Rotational Spectrum ◽  
Dual Frequency ◽  
One Dimensional ◽  
Ethyl Violet ◽  
Disperse Red 1 ◽  
Good Agreement

An original poling method using purely optical means and based on a dual-frequency interference process is presented. We show that the coherent superposition of two beams at fundamental and second-harmonic frequencies results in a polar field with an irreducible rotational spectrum containing both a vector and an octupolar component. This enables the method to be applied even to molecules without a permanent dipole such as octupolar molecules. After a theoretical analysis of the process, we describe different experiments aiming at light-induced noncentrosymmetry performed respectively on one-dimensional Disperse Red 1 and octupolar Ethyl Violet molecules. Macroscopic octupolar patterning of the induced order is demonstrated in both transient and permanent regimes. Experimental results show good agreement with theory.

scholarly journals Comparison of Experimental and Numerical Transient Drop Deformation during Transition through Orifices in High-Pressure Homogenizers

2021 ◽  
Vol 5 (3) ◽  
pp. 32
Author(s):  
Benedikt Mutsch ◽  
Peter Walzel ◽  
Christian J. Kähler
Keyword(s):  
High Pressure ◽  
Visual Analysis ◽  
Imaging Technique ◽  
Extensional Flow ◽  
Droplet Breakup ◽  
Experimental Results ◽  
Drop Deformation ◽  
Droplet Deformation ◽  
Shadow Imaging ◽  
Good Agreement

The droplet deformation in dispersing units of high-pressure homogenizers (HPH) is examined experimentally and numerically. Due to the small size of common homogenizer nozzles, the visual analysis of the transient droplet generation is usually not possible. Therefore, a scaled setup was used. The droplet deformation was determined quantitatively by using a shadow imaging technique. It is shown that the influence of transient stresses on the droplets caused by laminar extensional flow upstream the orifice is highly relevant for the droplet breakup behind the nozzle. Classical approaches based on an equilibrium assumption on the other side are not adequate to explain the observed droplet distributions. Based on the experimental results, a relationship from the literature with numerical simulations adopting different models are used to determine the transient droplet deformation during transition through orifices. It is shown that numerical and experimental results are in fairly good agreement at limited settings. It can be concluded that a scaled apparatus is well suited to estimate the transient droplet formation up to the outlet of the orifice.

Simulation of Sphere’s Motion Induced by Shock Waves

2012 ◽  
Vol 134 (10) ◽  
Author(s):  
Dan Igra ◽  
Ozer Igra ◽  
Lazhar Houas ◽  
Georges Jourdan
Keyword(s):  
Shock Waves ◽  
Drag Coefficient ◽  
Drag Force ◽  
Stationary Flow ◽  
Experimental Results ◽  
Experimental Findings ◽  
Sphere Drag ◽  
Simulation Scheme ◽  
Good Agreement

Simulations of experimental results appearing in Jourdan et al. (2007, “Drag Coefficient of a Sphere in a Non-Stationary Flow: New Results,”Proc. R. Soc. London, Ser. A, 463, pp. 3323–3345) regarding acceleration of a sphere by the postshock flow were conducted in order to find the contribution of the various parameters affecting the sphere drag force. Based on the good agreement found between present simulations and experimental findings, it is concluded that the proposed simulation scheme could safely be used for evaluating the sphere’s motion in the postshock flow.

Viscoelastic Deformation of PC/ABS Alloy

2007 ◽  
Vol 353-358 ◽  
pp. 1229-1232
Author(s):  
Z.N. Yin ◽  
L.F. Fan ◽  
Tie Jun Wang
Keyword(s):  
Dynamic Mechanical Analysis ◽  
Relaxation Modulus ◽  
Mechanical Analysis ◽  
Experimental Results ◽  
Viscoelastic Deformation ◽  
Dynamic Mechanical ◽  
Storage And Loss Moduli ◽  
Static Relaxation ◽  
Comparison Of The Results ◽  
Good Agreement

Dynamic Mechanical Analysis (DMA) and static relaxation tests are carried out to study the viscoelastic deformation of PC/ABS alloy with blending ratio of PC to ABS being 50/50. A modified approach is developed to calculate the relaxation modulus of PC/ABS alloy from the DMA experimental results of storage and loss moduli. Comparison of the results obtained from DMA and static relaxation tests is presented and good agreement is found.

Sign in / Sign up

Export Citation Format

Share Document