VOL. 13, NO. 6, MARCH 2018 ISSN 1819-6608 ARPN Journal of Engineering and Applied Sciences ©2006-2018 Asian Research Publishing Network (ARPN). All rights reserved. www.arpnjournals.com 2017 HALL CURRENT AND CHEMICAL REACTION EFFECTS ON FREE CONVECTIVE FLOW PAST AN ACCELERATED MOVING VERTICAL PLATE WITH RAMPED TEMPERATURE: FEM Siva Reddy Sheri 1 , K. Rajeshwar Reddy 2 , Anjan Kumar Suram 1 and M. Chenna Krishna Reddy 3 1 Department of Mathematics, GITAM University, Hyderabad Campus, Telangana, India 2 Department of Mathematics, Malla Reddy College of Engineering & Technology, Medchal, Telangana, India 3 Department of Mathematics, Osmania University, Hyderabad, Telangana, India E-Mail: sreddy7@yahoo.co.in ABSTRACT A numerical investigation has been adopted to study chemical reaction effect on free convective flow past an accelerated moving vertical plate with ramped temperature. The governing equations of flow, heat and mass transfer are solved by employing finite element method. Numerical results for the velocity, temperature and concentration distributions for various parametric values are reported graphically and discussed. The influence of various important parameters on primary skin-friction coefficient, secondary skin-friction coefficient and the Nusselt number are shown in a tabular form. The accuracy of the numerical method is validated by a direct comparison with previously published work and found that there is an excellent agreement between the results exists. Keywords: free convection, hall current, chemical reaction, ramped temperature, FEM. INTRODUCTION The phenomena of free convection arise in the fluid flow when temperature or concentration change causes density variation leading to buoyancy forces acting on the fluid elements. Natural convective flow is prevalent in many natural phenomena and has varied and wide range industrial applications. It plays a vital role in our environment. This can be seen in our everyday life in the atmospheric flow, which is driven by temperature or concentration differences. Natural processes such as vaporization of mist and fog, photosynthesis, drying of porous solids, transpiration, sea-wind formation and formation of ocean currents occur due to thermal and solutal buoyancy forces developed as a result of a difference in temperature or concentration or a combination of these two. Such configurations are also encountered in several practical systems for industry- based applications, viz., heat exchanger devices, cooling of molten metals, insulation systems, petroleum reservoirs, filtrations, chemical catalytic reactors and processes, nuclear waste repositories, desert coolers and wet bulb thermometers. Literature related to free convection flow has been undertaken by several authors. Chandran et al. [1] have studied unsteady hydromagnetic free convection flow with heat flux and accelerated boundary motion. Palani and Abbas [2] have investigated free convection MHD flow with thermal radiation from an impulsively started vertical plate. Abdul Gaffer et al. [3] have analyzed free convection flow and heat transfer of non-Newtonian tangent hyperbolic fluid from an isothermal sphere with partial slip. Abdul Gaffer et al. [4] have performed Computational analysis of magneto hydrodynamic free convection flow and heat transfer of non-Newtonian tangent hyperbolic fluid from a horizontal circular cylinder with partial slip. Nandkeolyar and Das [5] have examined MHD free convective radiative flow past a flat plate with ramped temperature in the presence of inclined magnetic field. Chandra Rajvanshi et al. [6] have investigated Effect of radiation and gravity modulation on unsteady MHD free convection flow through porous medium in slip-flow regime with entropy. The Hall affect creates the voltage difference across an electric conductor, cross ways to the current and perpendicular to the magnetic field. Edwin Herbert Hall discovered this effect in 1879. The characteristics of current in a conductor are responsible for the occurrence of Hall affect. This effect plays a prominent role in differentiating the positive and negative charges moving in opposite directions. Hall affect has proved that the electric current flows in metals by the moving electrons and not by protons. It is also shown by the Hall affect that the current in P-Type semiconductors is due to positive holes moving instead of negative electrons. Hall probes are used as magnetometers to measure magnetic fields or inspect materials by using magnetic flux leakage. Hall effect devices require amplification as they produce very low signals. They are suitable for laboratory instruments. Hall affect devices are resistant to contaminants like dust and water. In recent years many advances are taking place in improvising these devices. Other applications of these sensors include the rotating speed sensors in automobiles, cycles etc., they can be used for sensing fluid flows and can also be used for sensing pressure. Researchers and academicians have advanced their studies relating to problems involving Hall Current are: Satya Narayana et al. [7] have studied effects of Hall current and radiation absorption on MHD micro polar fluid in a rotating system. Effects of Hall current, radiation and rotation on natural convection heat and mass transfer flow past a moving vertical plate by Seth et al. [8]. Hall effects on an unsteady magneto-convection and radiative heat transfer past a porous plate by Das et al. [9].