الفهرس 
Chapter (1) IntroductionOnly 14 pages are availabe for public view
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Abstract
Free convection heat transfer from circular solid, hollow and hollow/perforated pin fin heat sinks with different geometries, heat fluxes and velocities is numerically studied using FLUENT ANSYS 16.0. The geometric dependence of heat transfers from heat sinks of solid and hollow/perforated fins with staggered pattern, attached on a fixed area heated base plate is discussed. A SIMPLE code is developed using control volume approach to solve governing equations (mass, momentum and energy), and the second order upwind technique is used. The results were carried out for a range of Rayleigh number, 9.3×106> Ra> 1.63×107 for free convection heat transfer study. The free convection study shows that the performance of the hollow/perforated fin heat sink is higher than that for the solid fin heat sink. It is also investigated that hollow/perforated fin array with inner-to-outer diameter ratio (Di/Do=1/2) and perforation diameter (dp= 6 mm) is the best sample giving the maximum performance and less amount of weight compared to the corresponding solid ones for that case studied where the Nu is higher than solid pin fin by 2.76%. In addition, the forced convection heat transfer for the presented solid and hollow/perforated pin fin heat sinks is also studied. This study is carried out over a range of velocities of 1, 3, 5, 7 and 9m/s. This forced study shows that the hollow/perforated fin heat sink is better than the solid one and the thermal performance increases with increasing the inner-to-outer diameter ratio and perforation diameter. The average of percentage improvement of hollow perforated fin array of Di/Do=1/2 and dp= 6 mm for this presented study is more compared to the other arrays of circulated perforated pin fins shown in this thesis where the thermal performance factor equal 4.8%. Screen reader support enabled.