الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The heat transfer and friction characteristics of a decaying swirl flow were investigated numerically for cylindrical furnaces. The swirling motion of the hot gases (carbon dioxide, water vapor, oxygen and nitrogen) can be produced by using tangential inlet technique as the guide vanes in practical applications. The vanes of the swirl generator can be adjusted to obtain different swirl intensities. The investigation is performed for the Reynolds number ranging from 10,000 to 60,000 under a constant wall temperature condition. Different guide van angles (0•, IS•, 30•, 45•and 60•) were used for the swirling flow. The tube length and diameter are selected as 1500 mm and 73.5 mm, respectively giving a length to-diameter ratio of IJD = 20.4. The inlet radius ratio was varied from 8 to 14.The three-dimensional, steady, turbulent and compressible flow inside the tube model was simulated using a fInite volume based CFD code FLUENT 6.3. An augmentation of up to 300 % in Nusselt number was obtained in the decaying swirl flow depending upon the Reynolds number and the vane angle. It was found that the performance of swirling flow is better than corresponding axial flow with high vane angles and relatively low Reynolds numbers.