Katsuhisa. M., “Heat transf’er in entry length of double pipes”, Int J. Heat Mass Transfer, Vol.2, PP.240-251,1961 .
 Hatton- A. P, & Quarmby, A. .”Heat Transler in the thermal entry length with laminar flow in an annulus”, lnt. J. Heat Mass Transfer, vol5. Pp973-980, 1962.
 Vilenskii. V. D., Meronov, Y. V. & Smirnov, V. p., “Numerical solution of the problem of Heat transfer in an annular channel”, High Temperature, 9, PP.699 -704, 1971.
 Feldman. E. E. .”The numerical solution of the combined thermal and hydrodynamic entrance region of an eccentric annular ducts”, Ph.Thesis, Carnegie-mlon University, Pittsburgh, 1974.
 Feldman. E. E., Hornbeck. R. W. & Osterle, J. F., “A Numerical solution of laminar developing flow in eccentric annular ducts”, Int. J. Heat Mass Transfer, Vol.25 ,No.2, PP. 23 l-241, 1982.
 Feldrnan, E. E. & Hornbeck, R. w. & osterle. J. F. .”A Numerical solution of developing temperature for laminar flow in eccentric annular ducts”, Int. J. heat Mass f’ransfer, Vol.25 ,No., ,pp.243-253,1982.
Tikrit Journal of Engineering Sciences (2007) 14(3) 1-24
Numerical Study for Buoyancy Effect On Developing in The Entrance Region Horizontal of Eccentric Annulus
|Mohammed H. Al-Mosawi||Gazinga F. Al-Barzinji||Ghassan F. Lattif|
|Mechanical Eng. Dept., University of Karbala’a, Iraq||Mechanical Eng. Dept., Kirkuk University, Iraq||Mechanical Eng. Dept., Tikrit University, Iraq|
In this research, a numerical study has been done to done to clarify the effect of the eccentric annulus of to two horizontal cylinders on the rate flow the behavior of the thermal boundary layer at the entrance. The research includes the study of the effect of the eccentric annulus percentage and its directions on the flow behavior when the internal cylinder. The theoretical analysis of the question includes the solving of Naver – Stoke and energy equations on the supposition that the flow is steady, fully developing hydrodynamic, and in the stage of thermal developing. The question has been numerically solved after the transformation of the Cartesian coordinates to the computational domain by applying body fitted coordinates. The results include a survey of the cylinder surface in many sites of annulus flow, where as it is appeared in that the bouncy force causes the secondary flow behaves none uniformly at the entrance. The Nusselt number average along the two cylinders is decreased with the increase of eccentricity as a result of narrowing in the flow area which diminishes the average of heat transfer quality. We also conclude that the increase of Rayleih number with the movement of the heated cylinder towards low causes the increase of the average of Rayleih number and the laminar flow changes to turbulent flow at the limited region of the entrance when Rayleih number increases or the eccentricity percentage with cylinder movement away from the perpendicular halfway axis but the disturbance vanishes in approaching to the fully developed heated region. A correlation relationship is extracted to find an average change of Nusselt number after the stability of flow in the fully developed region when the diameter of the internal cylinder equals to half of external.
Keywords: Annulus, Eccentric, Buoyancy Force, Horizontal.