In this section, we will investigate what factors, including viscosity, affect the rate of fluid flow. The precise definition of viscosity is based on laminar, or nonturbulent, flow. Before we can define viscosity, then, we need to define laminar flow and turbulent flow. Figure shows both types of flow.

Calculate the Reynolds number for an object moving through a fluid. Explain whether the Reynolds number indicates laminar or turbulent flow. Describe the conditions under which an object has a terminal speed. A moving object in a viscous fluid is equivalent to a stationary object in a flowing fluid stream.

The introduction of viscous forces requires a model to obtain a set of conditions on the flow field to express the viscous stress tensor, \({\tau }_{ij}\), as a function of the local velocity field. This stress tensor consists of the various stresses that can occur on an element of fluid.

on any surface, anywhere in the fluid, can be expressed in terms of a single scalar field p(v r ,t) provided there are no shear forces. This gives rise to the relatively simple form of the equation of motion for inviscid flow. When shear forces are present, as …

2018年5月2日 · Consider the flow of a viscous homogeneous fluid confined in the annulus between two infinitely long concentric circular cylinders of radii \(R_1\) and \(R_2 > R_1\) rotating with constant angular speeds \(\Omega _1\) and \(\Omega _2\), respectively.

This section provides readings, class notes, videos seen during class, and problems with solutions for three lectures on equations of viscous flow.

The introduction of viscous forces requires a model to obtain a set of conditions on the flow field to express the viscous stress tensor, [latex]{\tau }_{ij}[/latex], as a function of the local velocity field. This stress tensor consists of the various stresses that can occur on an element of fluid.

We call this property of fluids viscosity. Juice has low viscosity, whereas syrup has high viscosity. In the previous sections we have considered ideal fluids with little or no viscosity. In this section, we will investigate what factors, including viscosity, affect the rate of fluid flow.

Viscous flows occur when the effects of fluid viscosity are balanced by those arising from fluid inertia, body forces, and/or pressure gradients. In such flows, scaling analyses do not allow a priori neglect of any terms in the equations of fluid motion.

The term ‘absolute stress’ is used to indicate the actual stress (with the absolute pressure being the true pressure) rather than a modified stress to be defined in slide 12 in which the hydrostatic pressure is removed. Description of G. I.Taylor film on reversibility.