A simulation of fluid-structure interaction (FSI) and combined convective heat exchange is accomplished in an open trapezoidal cavity-channel. A non-Newtonian (power law fluid) is inspected within the laminar region. The heat source is simulated by an isothermal hot cavity bottom wall, whereas all the rest solid walls are perfectly insulated. A deformable baffle is fixed at the top wall of the channel and its free end extends towards the open cavity. The location of the deformable baffle on the top wall is varied. The baffle position is investigated together with Richardson number (Ri = 0.01-100) and power law index (n = 0.5-1.5). The problem was solved using finite element method with Arbitrary Lagrangian-Eulerian (ALE) technique. The results are compared with the non-baffled channel. The study shows that the proposed baffled channel enhances the heat transfer notably

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A modified approach for the analysis of torsional vibrations in some rotor systems using modified Holzer and Matlab techniques, by building a graphical user interface (GUI), has been developed. The specific objective of this work is to illustrate the applicability and usefulness of the modified approach and the Matlab GUI in analyzing the effects of torsional vibration on some well known rotor systems such as two, three, and five rotor systems. Well Known problems in the field of torsional vibration were analyze. The results illustrate that the developed approach and the GUI are very useful tools for engineers, designers, and analysts of vibration problems in rotor systems.

A two-dimensional numerical investigation on laminar forced convection is carried out to estimate the thermal and fluid field behavior of Al2O3-water nanofluid in a circular pipe with constant heat flux. In this study, the finite element method (FEM) is employed to analyze the continuity, momentum, and energy governing equations by using COMSOL Multiphysics 3.5a. Computations of heat transfer rates were performed for a range of Reynolds numbers (Re ≤ 2000), and (Pr= 5.42). The effects of Reynolds number and fraction volume of nanoparticle (ɸ≤ 5%) on the mean coefficient of convection (havg), pressure drop (∆P), and thermal-hydraulic performance are investigated. The computations indicate that Al2O3 nanoparticle usage augments the average coefficient of heat convection significantly, and which is increased by (10%) with maximum pressure loss (15%) for (ɸ=5%) and high Reynolds number when compared to the base fluid. The present model is validated with empirical Shah Equation and the results showed a good agreement.

Growing global energy demand has become worrying due to the fluctuating fossil fuel prices, the damage caused by the use of conventional fuels as the toxic emissions and global warming. Therefore, dependence on alternative and sustainable sources has become a pressing topic. In this paper will review the performance of solar chimney power plant, the parameters that affect on the performance, conversion efficiency and power output for a different collection of prototypes. During this study there are found that power output of the solar chimney power plant is directly proportional to increase of the height of the chimney, specifically when the solar chimney is sloped where the performances is better as well as the conversion efficiency. While increasing the diameter of collector will provide a big heating area which cause a decrease of air density due to rise in the air temperature under the solar collector which lead to increase the flow of driving force and the mass flow rate that causes an increase in the power output. Pressure drop is an important factor for identifying the maximum power output when the solar radiation is a constant which effect on thermodynamic properties. Therefore, the efficiency will increase with increasing the optimal proportion of pressure drop.