Newtonian Fluid Flow in a Long Vertical Converging Tube

作者：Weng Huei Chu^*; Kao Yuan Kai

来源：Journal of the Chinese Society of Mechanical Engineers, 2016, 37(1): 61-67.

• converging/diverging tube
• sudden contraction/expansion
• nozzle/diffuser
• convergent/divergent flow

It is desirable to understand the role of converging geometry in influencing the flow in fluidic devices with different driving mechanisms. In this study, a mathematical model is developed of the combined pressure- and gravity-driven flow of Newtonian fluids through a long vertical converging tube. The fully developed solutions of the flow field distributions as well as the corresponding characteristics are solved using a numerical method based on a reduced form of Navier-Stokes equations in a cylindrical coordinates system. The numerical results are validated experimentally by pressure drop measurements of water flow in a glass tube for differential volume flow rates pumped from different levels within a reservoir. It is found that the effect of converging geometry is to raise the nonlinearity of pressure distribution along the tube and the magnitudes of longitudinal and transversal velocities. This effect can be further enhanced by increasing the pressure drop, which linearly increased with the increasing volume flow rate.

• 出版日期2016-2