The natural Natural convection is the mode of heat transfer which occurs due to the existence of temperature gradient. It didn’t require any external agent such as fan, pump and blower; it not only saves energy but avoids unwanted noise. Enclosure is a square segment which is a regular geometry, found in a number of applications such as a fully filled duct pipes, electronic systems, computer technologies, air conditioning applications, lubrication system, solar collector, a sheet metal covered store, a solar air heater and a compact plate heat exchanger etc. The current study investigates laminar natural convection in a square enclosure with isothermal vertical walls along with two thin baffles at different positions on them and with adiabatic base and top of the enclosure. The domain is filled with air. This two- dimensional study focuses attention to understand changes in flow and temperature field development due to variation in position of baffles for each cases of Rayleigh number varies from 3.004x106 to 1.147x107 . The flow behaviour and thermal characteristics have been investigated in case 1 and case 2 through streamlines and isotherms respectively. Complete domain has been chosen for analysis. Asymmetric solutions are also observed for some of the cases. These results are confirmed by development of the corresponding convection loops and also by the variation of Average Nusselt number. Finally, the thesis report summarizes the effects of different parameters on rate of heat transfer. Key words: Heat Transfer, S

The cork oak extracted from oak trees is using in many areas for isolation purposes. Cork oak is a natural insulating material. Cork oak is using primarily in bottle industry in various fields such as bottle stopper, medicine, shoes, motor industry, floor coverings, heat and sound insulation systems. The physical and mechanical properties of this reinforced cork oak powder and vinyl ester composites were investigated. Cork oak is reinforcement material, and vinyl ester resin is matrix material. Methyl ethyl ketone peroxide (MEK) is hardener, LR 9000 is binder for surface modification of cork oak and dibutyltin dilaurate is catalyst. Tensile, impact, hardness, density and acoustic tests were performed on composite products. With the addition of cork oak, it was observed that the mechanical properties decreased and after a certain rate increased. However, it has been observed that the sound absorbance properties increase. According to the results it is suggested that it can be use as sound insulation material.

The cork oak extracted from oak trees is using in many areas for isolation purposes. Cork oak is a natural insulating material. Cork oak is using primarily in bottle industry in various fields such as bottle stopper, medicine, shoes, motor industry, floor coverings, heat and sound insulation systems. The physical and mechanical properties of this reinforced cork oak powder and vinyl ester composites were investigated. Cork oak is reinforcement material, and vinyl ester resin is matrix material. Methyl ethyl ketone peroxide (MEK) is hardener, LR 9000 is binder for surface modification of cork oak and dibutyltin dilaurate is catalyst. Tensile, impact, hardness, density and acoustic tests were performed on composite products. With the addition of cork oak, it was observed that the mechanical properties decreased and after a certain rate increased. However, it has been observed that the sound absorbance properties increase. According to the results it is suggested that it can be use as sound insulation material.

Specifying the depth profile of crystal defects in CZ silicon wafer is an important step in defect engineering. An effective evaluation of defect depth profile leads to the delineation of thermal history of silicon ingot during crystal growth. The evaluation methods for Crystal Originated Pits (COP) free zone and Bulk Micro Defects (BMD) denuded zone such as light scattering tomography (LST), optical microscopy (OM), and scanning surface inspection system (SSIS) with the repeated polish process are destructive and time consuming. The photoluminescence (PL) imaging developed maps the PL variation across the silicon wafer owing to the combination of PL spectroscopy and confocal optical microscopy. It is also compliant with in-line industrial metrology standards: non-destructive, fast, reliable, and high resolution. This study evaluates the PL Imaging developed by Semilab (En-Vision) comparing with the results of OM, LST, and SSIS methods [1–5].