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Andrianarison O.,Institute Superieur Of Lautomobile Et Des Transports | Benjeddou A.,Institute Superieur Of Mecanique Of Paris
European Journal of Computational Mechanics | Year: 2012

A partial-mixed special finite element (FE) is proposed for the static analysis of multilayer composite and functionally graded material plates. Using the Hamiltonian formalism, the three-dimensional elasticity equations are first reformulated so that a partial-mixed variational formulation, retaining as primary variables the translational displacements augmented with the transverse stresses only, is obtained; this allows, in particular, a straightforward fulfilment of the multilayer interfaces continuity conditions. After an only in-plane FE discretisation, the static problem is then reduced, for a single layer, to a Hamiltonian eigenvalue problem that is solved analytically, through the layer thickness, using the symplectic formalism; the multilayer solution is finally reached via the state-space method and the propagator matrix concept. The performance, in convergence and accuracy, of the proposed approach, applied to representative examples, is shown to be very satisfactory. © 2012 Taylor & Francis.

Abd Rahman M.R.,University of Technology Malaysia | Vernin G.,Institute Superieur Of Lautomobile Et Des Transports | Bakar A.R.A.,University of Technology Malaysia
Applied Mechanics and Materials | Year: 2014

Drum brake squeal is one of the most common and annoying types of brake noise and it usually falls in the frequency range between 0.5-16 kHz. Brake squeal continues to confront vehicle manufacturers where it not only leads to significant increase in the warranty costs but also may affect customer's perception on quality of the vehicle. Thus this paper attempts to prevent drum brake squeal by means of lining modifications. In doing so, finite element method is first employed and squeal noise will be then predicted using complex eigenvalue (CE) analysis. A good lining modification should be able to stabilize the drum brake assembly by shifting or reducing positive real parts toward zero or negative real parts in the eigenvalue analysis. Finally, laboratory squeal tests are conducted on the four proposed modifications to verify its effectiveness against squeal. © (2014) Trans Tech Publications, Switzerland.

Hussin M.H.,University of Technology Malaysia | Bakar A.R.A.,University of Technology Malaysia | Jamaluddin M.R.,University of Technology Malaysia | Szlapka R.,Institute Superieur Of Lautomobile Et Des Transports
International Journal of Vehicle Structures and Systems | Year: 2010

This paper presents the effects of brake lining thickness due to wear on drum brake squeal. Brake lining will be worn out and subsequently its thickness will be reduced after a few number of braking applications. Hence dynamic properties of the lining, such as its natural frequency, might be changed. In this work, two different sets of brake lining, i.e., new and worn lining are used to investigate its effect on squeal generation. First, modal testing is performed to determine natural frequencies of those brake linings at free-free boundary condition. Later, squeal tests are carried out using brake dynamometer and squeal frequency is measured up to 10 kHz. Several squeal results are plotted over brake operating conditions to observe the influence of different lining thickness. In addition to these, squeal mechanisms, i.e., modal coupling due to closeness of the natural frequency between drum brake components and negative damping due to negative friction-velocity slope that contribute to the squeal generation are also investigated and discussed. © 2010. MechAero Foundation for Technical Research & Education Excellence.

Gning P.B.,University of Lille Nord de France | Gning P.B.,Institute Superieur Of Lautomobile Et Des Transports | Delsart D.,ONERA | Mortier J.M.,ONERA | Coutellier D.,University of Lille Nord de France
Composites Part B: Engineering | Year: 2010

This paper presents results obtained from the experimental study on the behaviour of glass/epoxy butterfly-shaped specimens tested under pure shear and biaxial loadings using an Arcan device. Notch-to-notch longitudinally and perpendicularly oriented fibre specimens, respectively referred to as Mat31 and Mat32 ones have been tested with different loading angles ranging from 0° to 90°. The fracture mode was more or less repetitive for Mat31 specimens whereas it depended on the loading direction for Mat32 type, for which the number of cracks and the obliqueness relative to the notch-to-notch line, decreased as the test angle increased. The comparison of failure envelopes has demonstrated that Mat31 specimens are much more resistant whatever the loading angle. However, strengths at failure of Mat32 type are in good agreement with Hashin's failure criterion, for pure shear tests up to 30° loading angles. Mat31 specimens' failure stresses were overestimated by the criterion, although similarities in trends were noticed. © 2010 Elsevier Ltd. All rights reserved.

Liang S.,Institute Superieur Of Lautomobile Et Des Transports | Gning P.B.,Institute Superieur Of Lautomobile Et Des Transports | Guillaumat L.,Ecole Nationale Superieur dArts et Metiers
ICCM International Conferences on Composite Materials | Year: 2011

The aim of this study is to analyze the fatigue response of a flax reinforced composite. The laminates were fabricated from noncrimp dry flax fabric impregnated with an epoxy matrix and stacked under pressure. Tensile and in-plane shear specimens having [0/90]3S and [±45] 3S sequences respectively, were tested to measure the quasi-static properties. A moderate properties scattering of around 10 % was found. The fatigue tests were performed from 80% to 40% of the composite ultimate quasi-static tensile strengths (UTS). Established Wohler's curves fit well with the Stress- Number of cycles (S-N) behaviour of this biomaterial. Classical three-stage stiffness degradation with a total loss of 15 to 20 % was observed on [±45]3S specimens, while the stiffness evolution for [0/90]3S specimens revealed an increase of around 2 to 3 % of the material's stiffness.

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