PERTURBATION SOLUTION OF SECONDARY FLOW OF POWER-LAW FLUID IN HELICAL PIPES WITH CIRCULAR CROSS-SECTION  

作　　者：Cui Hai-qing, Wang Ke-liang Department of Petroleum Engineering, Daqing Petroleum Institute, Anda 151400, China Wu Fu-bing Department of Navy and Ocean Engineering, Harbin Engineering University, Harbin 150001, China Zheng Xiao-song Department of Pet 

出　　处：《Journal of Hydrodynamics》2001年第4期72-78,共7页水动力学研究与进展B辑（英文版）

摘　　要：In terms of tensor analysis technique, the Navier-Stokes equations in helical coordinate system were derived. A steady incompressible flow of power-law fluid in helical pipes at low Reynolds number was investigated by the perturbation method. A second order solution of secondary flow was worked out. The secondary flow characteristics in helical pipes are analyzed. The effects of the number Dn, curvature and torsion on the secondary flow at different flow parameters were discussed. The results show that the secondary flow pattern changes from a single vortex to two vortices as the number Dn increases at a given curvature and a given torsion. Because of the effect of torsion, the secondary flow pattern changes from two almost symmetrical vortices to a single vortex as the torsion of the helical pipe increases while the Reynolds number and curvature hold constant. The secondary flow pattern cannot be affected by the curvature of the helical pipe at a given Dn number.In terms of tensor analysis technique, the Navier-Stokes equations in helical coordinate system were derived. A steady incompressible flow of power-law fluid in helical pipes at low Reynolds number was investigated by the perturbation method. A second order solution of secondary flow was worked out. The secondary flow characteristics in helical pipes are analyzed. The effects of the number Dn, curvature and torsion on the secondary flow at different flow parameters were discussed. The results show that the secondary flow pattern changes from a single vortex to two vortices as the number Dn increases at a given curvature and a given torsion. Because of the effect of torsion, the secondary flow pattern changes from two almost symmetrical vortices to a single vortex as the torsion of the helical pipe increases while the Reynolds number and curvature hold constant. The secondary flow pattern cannot be affected by the curvature of the helical pipe at a given Dn number.

关 键 词：helical pipe secondary flow power-law fluid perturbation method 

分 类 号：TV134[水利工程—水力学及河流动力学]