International Journal of Technology and Innovation

International Research Journal of Mechanical Engineering Vol.  2 (12) pp. 268-279, December, 2014.  © International Scholars Journals

Full Length Research paper

Reconciliation of thermo mechanical strains into ideal resilience configuration of mechanical Assembly utilizing NSGA II and FE Simulation

*M. H. Ansari, Vishnu Mittal and E. A Singh

Department of Mechanical Engineering, University of Calicut, Malappuram, India.

E-mail: [email protected]

Accepted 28 November, 2014

Abstract

In the design of mechanical assembly, the dimension-chain tools take into account the manufacturing dispersion of the parts and assembly defects. This ensures the interchangeability of the different components and guarantees that an assembly can carry out different service functions, as it is modeled in infinitely rigid solids. However, this approach does not take thermo-mechanical effects and deformation due to inertia effects like gravity, angular velocity etc., into account. Most materials change length as they change temperature. As a result of this change, the dimensions and tolerances of a product become at variance with the design values. Hence, thermal effects must be taken into account when designing a product that will undergo temperature cycling and yet, the different operating regimes of an assembly make it indispensable that the effects caused by the thermodynamic cycle should be integrated. In this regard, a finite element model of a machine assembly is created in order to determine the deformation due to change in temperature and inertia effects. The aim of this article is to include the deformation determined by Finite element analysis in the dimension chain thereby controlling clearances in the mechanical assembly. The approach first generates a Cost-tolerance model using neural network where the inputs are parameters and tolerance levels. Then, Finite element analysis of the machine assembly is carried out. The deformation obtained by FEA is then included in the dimension chain. Finally, optimization is done using Non-dominated sorting genetic algorithm II (NSGA II). The results provide designers with optimal component parameters and tolerance values, and the critical components and the manufacturing cost. The approach can also guarantee that the parameter and tolerance values found remain within tolerance for the temperature variation. Then, the product can function as intended under a wide range of temperature conditions for the duration of its life.

Key words: Dimension chain, thermo mechanical tool, finite element analysis, neural network and NSGA II.

International Research Journal of Mechanical Engineering Vol.  2 (12) pp. 260-267, December, 2014.  © International Scholars Journals

Full Length Research Paper

New blend SOC-WCIP strategy for the examination of low pass channel

*Claude Alexandra, Honore Dumas and Thierry E. hugo

Mechanical and Manufacturing Engineering Department, Faculty of Engineering, University of Montpellier, Montpellier, France.

E-mail: [email protected]. 

Accepted 16 November, 2014

Abstract 

The combination of the Wave Concept Iterative Process (WCIP) method combined with the Short-Open Calibration SOC technique to micro strip discontinuity is presented. This SOC technique is directly accommodated in the WCIP method. It is used to remove the unwanted parasitic errors brought by the approximation of the impressed voltage sources and the feed lines. The WCIP is formulated in such a way that the port voltages and currents are explicitly represented through relevant network matrices. The scattering parameters of the filter structure can be obtained through the development and the simulation. This result for micro strip discontinuities is compared with the conventional WCIP method. These instructions provide you guidelines for preparing papers for International Journal. Use this document as a template and as an instruction set.

Key words: Short open calibration (SOC), wave concept iterative process (WCIP), micro strip discontinuity, third-order filter.

International Research Journal of Mechanical Engineering Vol.  2 (11) pp. 254-259, November, 2014. © International Scholars Journals

Full Length Research Paper

Acceleration motion of geometric and spherical particles in two dimensions and effects of continuous sedimentation rectangular tanks design

Hubert O. Kennedy

Mechanical and Manufacturing Engineering Department, Faculty of Engineering, University of Washington, Seattle, USA.

Email: [email protected]

Accepted 30 October, 2014

Abstract 

The design procedure outlined by Camp (1946) for design of continuous gravity sedimentation tank was revisited. The viscous effects of flowing fluid were included in the model by development of the velocity profile of the fluid in the horizontal direction. The transient motion of the spherical and geometric particles unhindered prior to reaching terminal settling velocity, was simulated using a desktop computer. The governing equations in two dimensions, vertical and horizontal were written in terms of velocity of the particle and the drag coefficient in transient motion was assumed to be of the same functional form as that obtained from empirical observations at steady state. The five constant expressions of Turton and Levenspiel (1989) was used and the trajectory of the particle was obtained relative to the motion of the fluid by use of fifth order Runge-Kutta method of numerical integration. As the density of the particle and size of the particle increases, the acceleration zone of the particles increased in size. Deeper tanks have to be constructed for such systems. The geometric particles reached their terminal settling velocities sooner compared with the spherical particles. The pressure drop, throughput and separation efficiency trade-offs are discussed.

Key words: Continuous gravity sedimentation, trajectory of particle, drag coefficient correlations, transition flow, fifth order Runge-Kutta method.

Key words: Oxy-hydrogen gas, alternative fuels.

International Research Journal of Mechanical Engineering Vol.  2 (10) pp. 242-246, October, 2014.© International Scholars Journals

Full Length Research Paper

Examination of the impact of air conduction on warmth exchange crosswise over Fibrous materials

*Guru Shankar, Ram R. Raj and Mohan E. T

Mechanical and Manufacturing Engineering Department, Faculty of Engineering, University of Kota, Kota India.

E-mail: [email protected]

Accepted 29 September, 2014

Abstract

Accurate prediction of the effective thermal conductivity of loose fill fibrous building thermal insulation remains a challenging issue to date. Most researchers considered the complex problem of heat transfer across a fibrous material to be the sum of heat transfer due to air conduction, solid conduction and radiation for which general empirical relationships were developed from reliable thermal conductivity tests. In this study, an experimental investigation of this hypothesis was undertaken by removing the air from a porous material, hence, theoretically leaving heat transfer due to solid conduction and radiation only. This hypothesis was tested by conducting steady state thermal conductivity measurements under vacuum conditions for coconut fiber and sugarcane fiber specimens. Test results indicated an average difference between the thermal conductivity at atmospheric conditions and under vacuum conditions of 0.0279 and 0.0231 W/m.K for coconut fiber and sugarcane fiber, respectively, over the density range tested. The experimental results were in agreement with the widely expressed opinion that air behaves as an independent individual contributor to the overall effective thermal conductivity of a loose fill fibrous material.

Key words: Fibrous insulation, thermal conductivity, loose fill insulation, effective thermal conductivity, air conduction.

International Research Journal of Mechanical Engineering Vol.  2 (10) pp. 236-241, October, 2014. © International Scholars Journals

Full Length Research Paper

Limited component examination of crisscross and easy chair sort single wall carbon nanotube

*Zhou S. Den-Yil, Yue A. Heng and chen Yip Man

 Mechatronics Engineering Department, Hong Kong Baptist University, Kowloon Tong, China

E-mail: [email protected].

Accepted 13 September, 2014

Abstract

A carbon nanotube (CNT) possesses superior mechanical, electrical and optical properties. The stiffness and flexibility is much higher than those of conventional fibers. Various investigators have carried out various experiments as well as theoretical analysis which show that the carbon nanotubes possess superior mechanical properties. The model development in this work is based on the assumption that carbon nanotubes, when subjected to loading, behave like space-frame structures. The bonds between carbon atoms are considered as connecting load-carrying members, while the carbon atoms as joints of the members. To create the finite element (FE) models, nodes are placed at the locations of carbon atoms and the bonds between them are modeled using ANSYS spring element. The present work predicts the Young’s modulus variation with respect to different wall thickness. The compiled result shows the Young’s modulus variation as well as the comparison of zigzag and armchair type of carbon nanotube due to different loading conditions. The results would act as a useful tool for developing new nano composites.

Key words: Finite element analysis, carbon nanotube (CNT), Young’s modulus.