الفهرس | Only 14 pages are availabe for public view |
Abstract The objective of the present investigation is to study the larninar combined convection heat transfer from an infinite isothennal horizontal circular cylinder. The combined convection where the forced flow can attack the horizontal circular cylinder at different angles was studied .A mathematical model was constructed which started from the conservation equations governing the transfer of continuity, momentum and thermal energy which were solved using the Patankar - Splading Technique [1]. A more accurate definition of the effective Reynolds number is obtained by combining the natural and forced convection flows vectorially instead of the pervious de~~on given by A.P .Hatton. The present work studies the effect of the angle of attack at different Reynolds and Grashofnumbers on the Nusselt number. A single correlation was obtained in the case of the laminar combined convection in the range of the Reynolds number from 40 to 300 and the effective Reynolds number from 50 to 1000. The study covered a wide range of the angle of attack from 00 (Assisting flow) to 1800 (Opposing flow). The Grashofnumber was varied from 100 to 1.69xl06, while keeping the Prandtl number constant at Pr = 0.7.The Nusselt number depends on the effective Reynolds number .The angle of attack for the same effective Reynolds number has no effect on the Nusselt number. |