IMPACT BEHAVIOR MODELING OF MOTORCYCLE FRONT WHEEL-TIRE ASSEMBLY

K. S. TAN,S. V. WONG,R. S. RADIN UMAR,N. K. GUPTA,A. M. S. HAMOUDA 한국자동차공학회 2009 International journal of automotive technology Vol.10 No.3

Experiments were conducted to investigate the influence of certain parameters that affect the impact response of the motorcycle front wheel-tire assembly under various impact conditions. Impact tests were conducted according to 2V 5–1 fractional factorial design using a pendulum impact test apparatus with impact speed, impact mass, tire inflation pressure level, striker geometry, and impact location as design factors. Significant factors influencing the response of the wheel-tire assembly were identified. Coefficients for each factor were also determined, and empirical models were then developed for each response. An analysis indicates that the developed models fit well within the experimental ranges of the respective factors. However, for several interaction effects, the models become unrealistic, whereby they give certain deformation values when approaching zero impact mass and/or zero impact velocity. This is not consistent with the mechanics of the physical world, as there should not be any significant deformation when delivered impact energy is small enough. Efforts have been made in developing better models to resolve the inconsistency and to include a wider range, especially considering the case of the lower limit of experimental factors, which are an impact mass of 51.18 kg and/or an impact velocity of 3 m s−1 (10.8 km/h) down to zero. The minimum amount of impact energy required to produce the onset of observable deformation on the wheel was incorporated in the development of new models. Finally, the present models have been developed not only to cover the lower regions but also to range up to the upper limits of the factors, which are an impact mass of 101.33 kg and an impact velocity of 6 m s−1 (21.6 km/h). Experiments were conducted to investigate the influence of certain parameters that affect the impact response of the motorcycle front wheel-tire assembly under various impact conditions. Impact tests were conducted according to 2V 5–1 fractional factorial design using a pendulum impact test apparatus with impact speed, impact mass, tire inflation pressure level, striker geometry, and impact location as design factors. Significant factors influencing the response of the wheel-tire assembly were identified. Coefficients for each factor were also determined, and empirical models were then developed for each response. An analysis indicates that the developed models fit well within the experimental ranges of the respective factors. However, for several interaction effects, the models become unrealistic, whereby they give certain deformation values when approaching zero impact mass and/or zero impact velocity. This is not consistent with the mechanics of the physical world, as there should not be any significant deformation when delivered impact energy is small enough. Efforts have been made in developing better models to resolve the inconsistency and to include a wider range, especially considering the case of the lower limit of experimental factors, which are an impact mass of 51.18 kg and/or an impact velocity of 3 m s−1 (10.8 km/h) down to zero. The minimum amount of impact energy required to produce the onset of observable deformation on the wheel was incorporated in the development of new models. Finally, the present models have been developed not only to cover the lower regions but also to range up to the upper limits of the factors, which are an impact mass of 101.33 kg and an impact velocity of 6 m s−1 (21.6 km/h).

Electrodeposition of flower-like platinum on electrophoretically grown nitrogen-doped graphene as a highly sensitive electrochemical non-enzymatic biosensor for hydrogen peroxide detection

Tajabadi, M.T.,Sookhakian, M.,Zalnezhad, E.,Yoon, G.H.,Hamouda, A.M.S.,Azarang, M.,Basirun, W.J.,Alias, Y. New York] ; North-Holland 2016 APPLIED SURFACE SCIENCE - Vol.386 No.-

An efficient non-enzymatic biosensor electrode consisting of nitrogen-doped graphene (N-graphene) and platinum nanoflower (Pt NF) with different N-graphene loadings were fabricated on indium tin oxide (ITO) glass using a simple layer-by-layer electrophoretic and electrochemical sequential deposition approach. N-graphene was synthesized by annealing graphene oxide with urea at 900<SUP>o</SUP>C. The structure and morphology of the as-fabricated non-enzymatic biosensor electrodes were determined using X-ray diffraction, field emission electron microscopy, transmission electron microscopy, Raman and X-ray photoelectron spectra. The as-fabricated Pt NF-N-graphene-modified ITO electrodes with different N-graphene loadings were utilized as a non-enzymatic biosensor electrode for the detection of hydrogen peroxide (H<SUB>2</SUB>O<SUB>2</SUB>). The behaviors of the hybrid electrodes towards H<SUB>2</SUB>O<SUB>2</SUB> reduction were assessed using chronoamperometry, cyclic voltammetry and electrochemical impedance spectroscopy analysis. The Pt NF-N-graphene-modified ITO electrode with a 0.05mgml<SUP>-1</SUP> N-graphene loading exhibited the lowest detection limit, fastest amperometric sensing, a wide linear response range, excellent stability and reproducibility for the non-enzymatic H<SUB>2</SUB>O<SUB>2</SUB> detection, due to the synergistic effect between the electrocatalytic activity of the Pt NF and the high conductivity and large surface area of N-graphene.

Physicochemical and photo-electrochemical characterization of novel N-doped nanocomposite ZrO₂/TiO₂ photoanode towards technology of dye-sensitized solar cells

Mohamed, Ibrahim M.A.,Dao, Van-Duong,Yasin, Ahmed S.,Mousa, Hamouda M.,Yassin, Mohamed A.,Khan, Muhammad Yasir,Choi, Ho-Suk,Barakat, Nasser A.M. Elsevier 2017 Materials characterization Vol.127 No.-

<P><B>Abstract</B></P> <P>This work introduces the synthesis of N-doped nanocomposite of ZrO<SUB>2</SUB>/TiO<SUB>2</SUB> nanofibers (NFs) by use of both electrospinning and hydrothermal methods. The physicochemical properties of the introduced TiO<SUB>2</SUB> NFs are investigated to describe the morphology, crystallinity and chemistry through FESEM, SEM-EDX, XRD, TEM and XPS. As the results, the investigated material can be described as N@ZrO<SUB>2</SUB>/TiO<SUB>2</SUB> NFs. The crystal structure of the prepared TiO<SUB>2</SUB> is only anatase structure. Then, the novel NFs are utilized to design novel photoanode and photo-electrochemical characterization such as current-potential response under light, incident photon-to-current efficiency (IPCE) and electrochemical impedance spectroscopy (EIS) of the dye-sensitized solar cell (DSC) are also investigated. The photovoltaic response showed that the efficiency of the DSCs employed N@ZrO<SUB>2</SUB>/TiO<SUB>2</SUB> photoanode gave 4.95%, which was higher than those of DSCs designed with ZrO<SUB>2</SUB>/TiO<SUB>2</SUB> NFs (4.51%) and N@TiO<SUB>2</SUB> NFs (4.41%) photoanodes. The high photo-response of DSC by use of N@ZrO<SUB>2</SUB>/TiO<SUB>2</SUB> NFs can be attributed to enhanced electrical conductivity, which is studied via EIS, and presence of active sites of N. These active sites can easily absorb dye-molecules in the step of dye-loading in the fabrication of DSC.</P> <P><B>Highlights</B></P> <P> <UL> <LI> N-doped ZrO<SUB>2</SUB>/TiO<SUB>2</SUB> nanofibers (NFs) are synthesized via facile two steps; electrospinning followed by hydrothermal. </LI> <LI> The produced NFs have only anatase crystal structure. </LI> <LI> 4.95% PV efficiency was achieved by the synthesized NFs. </LI> <LI> DSC based on N-doped ZrO<SUB>2</SUB>/TiO<SUB>2</SUB> NFs shows high electrical conductivity and low charge transfer resistance; 9.375Ω. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Investigating nonlinear forced vibration behavior of multi-phase nanocomposite annular sector plates using Jacobi elliptic functions

Seyed Sajad Mirjavadi,Masoud Forsat,Mohammad Reza Barati,A.M.S. Hamouda 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.36 No.1

A multi-scale epoxy/CNT/fiberglass annular sector plate is studied in this paper in the view of determining nonlinear forced vibration characteristics. A 3D Mori-Tanaka model is employed for evaluating multi-scale material properties. Thus, all of glass fibers are assumed to have uni-direction alignment and CNTs have random diffusion. The geometry of annular sector plate can be described based on the open angle and the value of inner/outer radius. In order to solve governing equations and derive exact forced vibration curves for the multi-scale annular sector, Jacobi elliptic functions are used. Obtained results demonstrate the significance of CNT distribution, geometric nonlinearity, applied force, fiberglass volume, open angle and fiber directions on forced vibration characteristics of multi-scale annular sector plates.

Assessment of transient vibrations of graphene oxide reinforced plates under pulse loads using finite strip method

Seyed Sajad Mirjavadi,Masoud Forsat,Mohammad Reza Barati,A.M.S. Hamouda 사단법인 한국계산역학회 2020 Computers and Concrete, An International Journal Vol.25 No.6

Based on a refined shear deformation finite strip, transient vibrations of graphene oxide powder (GOP) reinforced plates due to external pulse loads have been investigated. The plate has uniformly and linearly distributed GOPs inside material structure. Applied pulse loads have been selected as sinusoidal, linear and blast types. Such pulse loads result in transient vibrations of the GOP-reinforced plates which are not explored before. Finite strip method (FSM) has been performed for solving the equations of motion and then inverse Laplace transform technique has been employed to derive transient responses due to pulse loading. It is reported in this study that the transient responses of GOP-reinforced plates are dependent on GOP dispersions, GOP volume fraction, type of pulse loading, loading time and load locations.

Wave propagation in a 3D fully nonlinear NWT based on MTF coupled with DZ method for the downstream boundary

Xu, G.,Hamouda, A.M.S.,Khoo, B.C. Techno-Press 2014 Ocean systems engineering Vol.4 No.2

Wave propagation in a three-dimensional (3D) fully nonlinear numerical wave tank (NWT) is studied based on velocity potential theory. The governing Laplace equation with fully nonlinear boundary conditions on the moving free surface is solved using the indirect desingularized boundary integral equation method (DBIEM). The fourth-order predictor-corrector Adams-Bashforth-Moulton scheme (ABM4) and mixed Eulerian-Lagrangian (MEL) method are used for the time-stepping integration of the free surface boundary conditions. A smoothing algorithm, B-spline, is applied to eliminate the possible saw-tooth instabilities. The artificial wave speed employed in MTF (multi-transmitting formula) approach is investigated for fully nonlinear wave problem. The numerical results from incorporating the damping zone (DZ), MTF and MTF coupled DZ (MTF+DZ) methods as radiation condition are compared with analytical solution. An effective MTF+DZ method is finally adopted to simulate the 3D linear wave, second-order wave and irregular wave propagation. It is shown that the MTF+DZ method can be used for simulating fully nonlinear wave propagation very efficiently.

Numerical simulation of fully nonlinear sloshing waves in three-dimensional tank under random excitation

Xu, Gang,Hamouda, A.M.S.,Khoo, B.C. Techno-Press 2011 Ocean systems engineering Vol.1 No.4

Based on the fully nonlinear velocity potential theory, the liquid sloshing in a three dimensional tank under random excitation is studied. The governing Laplace equation with fully nonlinear boundary conditions on the moving free surface is solved using the indirect desingularized boundary integral equation method (DBIEM). The fourth-order predictor-corrector Adams-Bashforth-Moulton scheme (ABM4) and mixed Eulerian-Lagrangian (MEL) method are used for the time-stepping integration of the free surface boundary conditions. A smoothing scheme, B-spline curve, is applied to both the longitudinal and transverse directions of the tank to eliminate the possible saw-tooth instabilities. When the tank is undergoing one dimensional regular motion of small amplitude, the calculated results are found to be in very good agreement with linear analytical solution. In the simulation, the normal standing waves, travelling waves and bores are observed. The extensive calculation has been made for the tank undergoing specified random oscillation. The nonlinear effect of random sloshing wave is studied and the effect of peak frequency used for the generation of random oscillation is investigated. It is found that, even as the peak value of spectrum for oscillation becomes smaller, the maximum wave elevation on the side wall becomes bigger when the peak frequency is closer to the natural frequency.

Thermal vibration of two-dimensional functionally graded (2D-FG) porous Timoshenko nanobeams

Seyed Sajad Mirjavadi,Behzad Mohasel Afshari,Navvab Shafiei,A.M.S. Hamouda,Mohammad Kazemi 국제구조공학회 2017 Steel and Composite Structures, An International J Vol.25 No.4

The thermo-mechanical vibration behavior of two dimensional functionally graded (2D-FG) porous nanobeam is reported in this paper. The material properties of the nanobeam are variable along thickness and length of the nanobeam according to the power law function. The nanobeam is modeled within the framework of Timoshenko beam theory. Eringen\'s s nonlocal elasticity theory is used to develop the governing equations. Using the generalized differential quadrature method (GDQM) the governing equations are solved. The effect of porosity, temperature distribution, nonlocal value, L/h, FG power indexes along thickness and length and are investigated using parametric studies.

Analyzing exact nonlinear forced vibrations of two-phase magneto-electro-elastic nanobeams under an elliptic-type force

Mirjavadi, Seyed Sajad,Nikookar, Mohammad,Mollaee, Saeed,Forsat, Masoud,Barati, Mohammad Reza,Hamouda, A.M.S. Techno-Press 2020 Advances in nano research Vol.9 No.1

The present paper deals with analyzing nonlinear forced vibrational behaviors of nonlocal multi-phase piezo-magnetic beam rested on elastic substrate and subjected to an excitation of elliptic type. The applied elliptic force may be presented as a Fourier series expansion of Jacobi elliptic functions. The considered multi-phase smart material is based on a composition of piezoelectric and magnetic constituents with desirable percentages. Additionally, the equilibrium equations of nanobeam with piezo-magnetic properties are derived utilizing Hamilton's principle and von-Kármán geometric nonlinearity. Then, an exact solution based on Jacobi elliptic functions has been provided to obtain nonlinear vibrational frequencies. It is found that nonlinear vibrational behaviors of the nanobeam are dependent on the magnitudes of induced electrical voltages, magnetic field intensity, elliptic modulus, force magnitude and elastic substrate parameters.

Nonlocal strain gradient effects on forced vibrations of porous FG cylindrical nanoshells

Mirjavadi, Seyed Sajad,Forsat, Masoud,Nia, Alireza Farrokhi,Badnava, Salman,Hamouda, A.M.S. Techno-Press 2020 Advances in nano research Vol.8 No.2

The present paper explores forced vibrational properties of porosity-dependent functionally graded (FG) cylindrical nanoshells exposed to linear-type or triangular-type impulse load via classical shell theory (CST) and nonlocal strain gradient theory (NSGT). Employing such scale-dependent theory, two scale factors accounting for stiffness softening and hardening effects are incorporated in modeling of the nanoshell. Two sorts of porosity distributions called even and uneven have been taken into account. Governing equations obtained for porous nanoshell have been solved through inverse Laplace transforms technique to derive dynamical deflections. It is shown that transient responses of a nanoshell are affected by the form and position of impulse loading, amount of porosities, porosities dispensation, nonlocal and strain gradient factors.