A STUDY ON THE UNSTEADY FLOW IN A HELICAL PIPE

• Published in: Applied mathematics and mechanics Vol. 24; no. 5; pp. 585 - 595
• Main Author: 章本照 马赛璞 苏霄燕 张金锁
• Format: Journal Article
• Language: English
• Published: College of Life Science, Hebei University, Baoding, Hebei 071002, P.R. China 01.05.2003; Departnent of Mechanics, Zhejiang University, Hangzhou 310027, P.R. China%Departnent of Mechanics, Zhejiang University, Hangzhou 310027, P.R. China
• Subjects: Womersley数; 不稳定低频振动流; 双参数扰动; 扰动解; 控制方程; 螺旋管; 轴压力梯度; helical pipe; oscillatory flow; perturbation method
• ISSN: 0253-4827; 1573-2754
• DOI: 10.1007/BF02435871

A study on the unsteady low-frequency oscillatory flow in a helical circular pipe is carried out based upon the blood flow in vessels,using the method of bi-parameter perturbation.The second order perturbation results were obtained and the characteristics were analyzed at different time of the axial velocity,of the secondary flow,and of the wall shearing stress.Also done the analysis of above-mentioned variables that varied along with time and Womersley number.The results indicate that for a helical pipe,the torsion exerts the main influence on the distribution of secondary flow velocity,especially when the absolute value of axial press gradient is rather small.The severe variation of stream function takes place within a very short period,during which time the stream function develops from positive value to negative value and vice versa,while in most cases in a cycle,the variation is smooth.The wall shearing stress changes severely with theta too.