双筒流变仪中Burger流体流动分析

Analysis of Burgers fluid flow in double cylinder rheometer

该文研究了双筒流变仪中Burger流体非稳态流动,应用Hankel变换得到了双筒流变仪中Burger流体非稳态流动的解析解,据此可分析环管内旋转速度和切应力分布与变化特征。利用Laplace变换数值反演Stehfest方法分析了流变仪中Burger流体的动态特征,结果表明速度场和应力场分布对Burger流体参数非常敏感。Navier-Stokes流体的著名解,像Maxwell流体、二阶流体和Oldroyd-B流体的解都是本文解的特殊情况.

This paper deals with some unsteady transient flows of a Burger＇s fluid in a double cylinder rheometer. Analytical solution for some unsteady flows of Burger＇s fluid in a double rheometer was given by using Hankel transform. The formulae can be used to analyze the behavior of unsteady flow of Burgers＇ fluid in a double cylinder rheometer. The characteristic of Burger＇s fluid flow in the rheometer was analyzed by using Stehfest method of the numerical inversion of Laplace transform. The result indicates that the more sensitive is the dependence of velocity and stress on the value of Burger＇s fluid parameter. The well known solutions for a Navier-Stokes fluid,as well as those corresponding to a Maxwell fluid, a second grade and an Oldroyd-B one fluid, appear as limiting cases of our solutions.