Unsteady free convection on a horizontal circular cylinder in the presence of heat generation and radiation

• Main Author: Zainuddin, Najahulfazliah
• Format: Thesis
• Language: English; English; English
• Published: 2014
• Subjects: QC Physics; QC251-338.5 Heat
• Online Access: http://eprints.uthm.edu.my/1594/1/24p%20NAJAHULFAZLIAH%20ZAINUDDIN.pdf; http://eprints.uthm.edu.my/1594/2/NAJAHULFAZLIAH%20ZAINUDDIN%20COPYRIGHT%20DECLARATION.pdf; http://eprints.uthm.edu.my/1594/3/NAJAHULFAZLIAH%20ZAINUDDIN%20WATERMARK.pdf; http://eprints.uthm.edu.my/1594/

The unsteady free convective flow about a horizontal circular cylinder in the presence of heat generation and radiation is considered in this thesis. The cylinder is fixed and immersed in a Newtonian fluid, while the temperature at the surface is either heated uniformly or oscillated harmonically about the mean temperature, temperature of the surrounding. In this study, the governing equations are first transformed into a non-dimensional form by using appropriate non-dimensional variables. These equations are then transformed into a system of nonlinear partial differential equations, then were solved numerically by using two types of finite difference methods namely explicit finite difference method and implicit finite difference scheme of Crank Nicolson method. The solutions obtained by those two methods are used to compare the accuracy between them with the previous studies. The presence of heat generation significantly gives effect which increased the local skin-friction coefficient, temperature and velocity distribution but the local rate of heat transfer decreases. While, the presence of radiation increase the local rate of heat transfer, skin-friction coefficient, the temperature and velocity distributions. On the other hand, as the Prandtl number increases, the temperature and velocity distributions are decreases. This study also presents the temperature patterns for the problems when the temperature of the surface is heated and oscillated with respect to time. The comparison between the presence of radiation, heat generation and both of radiation and heat generation on temperature profiles against time are presented. It would be interesting when this study extended by involving the effect of magnetic field on this study and solve the related problems by using other numerical method.