الفهرس 
CHAPTER (1): INTRODUTIONOnly 14 pages are availabe for public view
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Abstract
The combined conduction and convection heat transfer produced by flow around a horizontal cylinder is, experimentally and numerically, investigated. When conduction in the solid wall and convection in the adjacent fluid occurs simultaneously, the process is called conjugate heat transfer and it arises due to the finite thickness of the wall. In many practical applications, such as heat exchangers, power plants, cooling of electrical and electronic equipments, pipe insulation systems, etc., the effect of conduction within the solid wall is significant and must be taken into account. In this study two cases are considered; the first is the conjugate conduction-free convection heat transfer from circular cylinder and the second is the conjugate conduction-forced convection heat transfer from the circular cylinder. For each of the two cases, equations of fluid motion and energy for flow and solid wall are numerically solved to determine the characteristics of the flow and thermal fields. In case of steady conjugate conduction-free convection heat transfer, the controlling parameters including, beside Rayleigh number and Prandtl number, both the thermal conductivity ratio and diameter ratio are considered. The effect of these parameters on heat transfer process is investigated. The study has shown, that the existence of critical radius for some values of Rayleigh number and thermal conductivity ratio. Furthermore, the experimental work is conducted for this case for some values of Rayleigh number. The study has shown acceptable agreement between present experimental and theoretical results. Similarly, in case of conjugate conduction-forced convection problem, the effect of controlling parameters, such as Reynolds number, Prandtl number, thermal conductivity ratio and diameter ratio on heat transfer process are investigated. In this case, the vortex shedding phenomenon has been predicted and its effect on the flow and thermal fields has been determined. Vortex shedding usually occurs at Reynolds number above 40. The study has shown, that the vortex shedding process introduces oscillating component to lift and drag forces as well as rate of heat transfer from the cylinder. For verification of the proposed model, the present theoretical results are compared with previously published experimental and theoretical data and good agreements were found.