文档介绍：Mechanics of Fluid
Chapter 7
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第七章粘性流体动力学基础
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Chapter 7 Fundament of viscosity liquid dynamics
§7–1 Introduction
§7–2 Dynamic differential equation of viscosity liquid-Navier-Stokes equation
§7–3 Axial flowing between two concentric cylinder
§7–4 Flow between two parallel plates
§7–5 Flow around a sphere Flow with minor Reynolds number
§7–6 Fundamental equation of turbulent flow—Reynolds equation
Chapter 7 exercises
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第七章粘性流体动力学基础
§7–1 引言
§7–2 粘性流体的运动微分方程
——纳维—斯托克斯方程
§7–3 两同心圆柱间的轴向流动
§7–4 两平行平板间的流动
§7–5 绕圆球的小雷诺数流动
§7–6 紊流的基本方程—雷诺方程
第七章习题
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Chapter 7 Fundament of viscosity liquid dynamics
§7-1 Introduction
Fundament of viscosity liquid dynamics
Real liquid in nature takes on viscosity,so study dynamics of viscosity liquid is important to project.
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第七章粘性流体动力学基础
§7-1 引言
粘性流体动力学基础
自然界中的真实流体都是具有粘性的,因此研究粘性流体的动力学问题,对于工程实际有着重要的意义。
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§7-2 Dynamic differential equation of viscosity liquid
——Navier—Stokes equation
In balanced or dynamic ideal fluid ,surface force act on fluid micro-group only pressive stress(pressure) that normal to surface,pressive stress takes on a little in dynamic viscosity fluid , because of influence of viscosity,surface force act on fluid micelle is not pressive stress but also shear stress . pressive stress at one point does not take on isotropy any as figure(7—1),because surface force have ponent in each infinitesimal,so one point in real fluid , such as stress of point A in figure can be expressed with stress posed of nine elements.
一、stress in viscosity fluid
Fundament of viscosity liquid dynamics
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§7-2 粘性流体的运动微分方程
——纳维—斯托克斯方程
在平衡流体或运动的理想流体中,作用在流体微团上的表面力只有与表面相垂直的压应力(压强),而且压应力又具有一点上各向同性的性质。但在运动的粘性流体中,由于粘性的影响,作用在流体微团上的表面力不仅有压应力还有切应力。而且一点上的压应力也不在具有各向同性的性质了。如图(7—1)所示,因为每个微元表面上的表面力都有三个分量,故而实际流体中一点,例如图中A点上的应力可用九个元素组成的一个应力矩阵
粘性流体动力学基础
一、粘性流体中的应力
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(7—1)
Called two rank symmetrical stress
of normal stress of its diagonal is invariable of stress tensor.
definition:
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