Solutions for Unsteady Unidirectional Flow of a Generalized Burger Fluid in an Annular Pipe With Different Given Volume Flow Rate Conditions

The velocity profile and pressure gradient of the unsteady state unidirectional flow of a generalized Burger fluid in an annular pipe with different given volume flow rate conditions are investigated in this study. Traditional models of this fluid is often solved by a partial (or ordinary) differential equation (PDE/ODE) with initial values or some boundary conditions. However, it is not enough to describe the phenomenon of Burger fluid in the real case. In this research, we added the inlet volume flow rate as an initial condition of the PDE. In order to understand the different flow characteristics, two basic flow situations are solved based on the prescribed flow conditions including a suddenly started flow and a constant accelerated flow, respectively. Finally, the linear acceleration and oscillatory flow is also considered in the last two cases. © 2020, Chinese Mechanical Engineering Society. All right reserved.