Nonlinear Vibration Analysis of an Electrostatically Actuated Microbeam using Differential Transformation Method

In this paper, nonlinear vibration of electrostatically actuated microbeam is analyzed using differential transformation method.The high level of accuracy of the analytical solutions of the method was established through comparison of the results of the solutions of exact analytical method, variational approach, homotopy analysis method and energy balance methods. Also,with the aid of the present analytical solution, the time response, velocity variation and the phase plots of the system are presented graphically. It is hope that the method will be widely applied to more nonlinear problems of systems in various fields of study.

An Investigation of the Effects of Manufacturing Parameters On Properties of Binderless Boards Produced from Abura (Mitragyna Ciliata) Sawdust

The production of particle boards without the use of synthetic binders is desirable to prevent environmental problems. This study has produced experimental binderless boards from untreated sawdust from Abura wood using a laboratory press. Box-Behnken experimental design was utilized to investigate the effects of the pressing variables including pressure, temperature and pressing time. The density of the boards produced ranged between 523.69 and 738 kg/m3 which was within the range specified for medium density fibreboards . The maximum values for Modulus of Elasticity (MOE), Modulus of Rupture (MOR) and Internal Bonding Strength (IB) were 100.4 MPa, 1.1 MPa and 0.049 MPa, respectively. It was shown that, for the range of factors studied, pressure and the pressing temperature were the more significant factors in determining the density, MOE and IB. This study showed that the sawdust can potentially be used for the production of binderless boards

An Investigation of the Effects of Manufacturing Parameters On Properties of Binderless Boards Produced from Abura (Mitragyna Ciliata) Sawdust

The production of particle boards without the use of synthetic binders is desirable to prevent environmental problems. This study has produced experimental binderless boards from untreated sawdust from Abura wood using a laboratory press. Box-Behnken experimental design was utilized to investigate the effects of the pressing variables including pressure, temperature and pressing time. The density of the boards produced ranged between 523.69 and 738 kg/m3 which was within the range specified for medium density fibreboards . The maximum values for Modulus of Elasticity (MOE), Modulus of Rupture (MOR) and Internal Bonding Strength (IB) were 100.4 MPa, 1.1 MPa and 0.049 MPa, respectively. It was shown that, for the range of factors studied, pressure and the pressing temperature were the more significant factors in determining the density, MOE and IB. This study showed that the sawdust can potentially be used for the production of binderless boards

Numerical Forced Convection Heat Transfer, Fluid Flow and Entropy Generation Analyses of Al2O3-Water Nanofluid in Elliptical Channels

This study investigates a three-dimensional elliptical microchannel heat sink for heat dissipation in laminar forced convection. The study seeks to improve thermal performance and overcome overheating associated with excessive temperature commonly experienced in heat-generating equipment, which is beyond the temperature usually specified by the manufacturer. The objective of the study is to evaluate the heat transfer, fluid flow, and entropy generation characteristics of Al2O3-water nanofluid in an elliptical cooling channel. The numerical analysis is investigated on the structure experiencing constant volumetric heat generation. The parameters considered are Reynolds number of 100 ≤ Re ≤ 500, nanoparticle concentration ϕ, from 0% to 4% with channel aspect ratio Ar from 1 to 3. The impacts of these parameters on the maximum temperature, heat transfer coefficient, friction factor, and volumetric entropy generation are reported. The study demonstrates that heat transfer is enhanced in the elliptical cooling channel at different aspect ratios, nanoparticle concentrations, and Reynold numbers. The results showed that as the nanoparticle concentration, channel aspect ratio, and Reynolds number (Re) increase, the maximum temperature, and total entropy generation decrease. As the channel aspect ratio increases at a specified Re = 200 and nanofluid concentration, ɸ = 3%, the maximum temperature, and total entropy generation decrease by up to 62% while the heat transfer coefficient increases by up to 78% and the friction factor increase by less than 2% with aspect ratio. However, the friction factor is not sensitive to the nanofluid concentration as a coolant