IMECE2009-12186 APPLICATION OF THE EXTENDED KANTOROVICH METHOD TO THE VIBRATIONAL ANALYSIS OF ELECTRICALLY ACTUATED MICROPLATES

ABSTRACT This paper presents an extended Kantorovich approach to investigate the vibrational behavior of electrically actuated rectangular microplates. The model accounts for the electric force of the excitation and for the applied in plane loads. Starting from a one term Galerkin approximation and following the extended Kantorovich procedure, the partial differential equation governing the microplate vibration, is discretized to two ordinary differential equation with constant coefficients. These equations are then solved analytically and iteratively with a rapid convergence procedure for finding microplate natural frequencies and modeshapes. Results in some specific cases are validated against other theoretical results reported in the literature. It is shown that rapid convergence, high precision and independency of initial guess function make the EKM an effective and accurate design tool for design optimization

A COMPARISON OF THE RELATIVE EFFECTIVENESS OF FIN ASPECT RATIO UNDER NATURAL CONVECTIVE HEAT TRANSFER WITH TOP MOUNTED FINS IMECE2009-12364

ABSTRACT Mechanical engineers often design fins on metal enclosures to dissipate an internal heat load using natural convection. This paper gives the results of a series of CFD (Computational Fluid Dynamics) studies, and, supporting calculations for the maximum temperature rise on a plate with a constant heat load of 100 watts applied to the bottom of the plate. Vertical fins are formed on the top surface of the plate. In this study, the horizontal dimensions and thickness of a square plate are held constant, while, the aspect ratio of the top surface fins are varied between studies. The aspect ratio is defined as the ratio of the height of the fin to the width of the base of the fin. The study compares aspect ratios from 1:1 to 40:1 with a constant base width. In addition, comparisons between 20:1 aspect ratio fins with the same height but with different fin counts due to changes in fin separation distances are compared. Closely spaced fins are not always the best solution for natural convection. DISCUSSION In this study, a series of fins were constructed on 12 by 12 by 0.125 thick, inch plates. The base of the plate was loaded with a constant heat load. The plate was placed on a sand base inside of a 50 by 50 by 50 inch buoyant air volume. The outer walls of the air volume were given a film coefficient of 100 BTU/Sq-Ft-F, a temperature of 45 degrees centigrade, and a slip boundary condition, i.e. no mass transfer across, and, a frictionless surface face. The bottom surface of the sand was set to a constant temperature of 45 degrees centigrade. These conditions represent a very large heat sink or volume of air as seen out doors, or, in typical room in a building. For the first study, the bases of the fins were constructed with a constant width of 0.125 inches, and, the fins were separated by 0.250 inches. The fins extended the full width of the 12 inch dimension of the plates. (Se

A STUDY NUMERICAL SIMULATION OF POST COMBUSTION CO 2 CAPTURE PROCESS

ABSTRACT Amine absorption technology, in particular that based on the Monoethanolamine (MEA) process, is considered to be viable for low pressure flue gas CO 2 capture because of the MEA-CO 2 fast reaction rate. MEA absorption processes are associated with high capital and operating cost because a significant amount of energy is required for solvent regeneration and severe operating problems are present such as corrosion and solvent loss and degradation. The overall objective of this study is to evaluate the feasibility of obtaining the heat required for amine absorption for a particular recovery of carbon dioxide. Comparisons among cases were performed to determine the best operating conditions for CO 2 capture. An analysis of the lean loading and recovery percent were carried out as well as the different absorber and stripper combinations by using the chemical processes simulator