第六章 不可压缩理想流体的无旋运动.ppt

Mechanics of Fluid
Chapter 6
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第六章不可压缩理想流体的无旋运动
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Chapter 6 Irrotational flow of impressible ideal-fluid
§6–1 Introduction
§6–2 Dynamic analysis of micelle in liquid
§6 –3 Velocity potential of irrotational flow
§6–4 Stream function of plane flow
§ 6–5 Fundamental potential flow in plane
§ 6–bining theory of potential flow
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第六章不可压缩理想流体的无旋运动
§6–1 引言
§6–2 流体微团运动分析
§6 –3 无旋流动的速度势
§6–4 平面流动的流函数
§ 6–5 基本平面势流
§ 6–6 势流的叠加原理
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Chapter 6 Irrotational flow of impressible ideal-fluid
§6-1 Introduction
Irrotational flow of impressible ideal-fluid
In this chapter irrotational flow in plane of impressible ideal-fluid is studied, velocity field of irrotational flow can be obtained through three approach by calculating velocity potential, stream function bining potential.
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第六章不可压缩理想流体的无旋运动
§6-1 引言
不可压缩理想流体的无旋运动
本章主要研究不可压缩理想流体平面无旋运动,平面无旋运动的速度场可通过计算速度势、流函数及复势这三条途径来确定。
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§6-2 Dynamic analysis of liquid micelle
Known from theory mechanics,in rigid body there are two motion forms:moving and rotation;but different in liquid to different velocity of each point of liquid micelle in flow field,but need keep its continuity as well,so besides moving and rotation in liquid micelle,still has deform following three motion forms of liquid micelle are analyzed.
Figure 6—1 is plane motion of liquid liquid micelle is rectangle ABCD at t ,Through ,it changes into new position and deforms to ,again supposing at t velocity of angle point A is ,spreading due to Thaler progression,obtaining velocity of point B and C
Irrotational flow of impressible ideal-fluid
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§6-2 流体微团运动分析
由理论力学可知,刚体有平移和旋转两种运动形式,而流体运动则不同。由于流体微团在流场中各点的速度不同,但又要保持流体本身的连续性,因此流体微团除有平移和旋转运动外,还有变形运动。下面将分析流体微团的三种运动形式。
不可压缩理想流体的无旋运动
如图6—1所示的平面运动中的流体微团。设在 t 时刻流体微团为矩形ABCD,经过时段后它移动到新的位置并变形为,又设 t 时刻角点A的速度为,根据泰勒级数展开,得B、C点的速度分别为
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Figure 6-1 Analysis on plane motion of liquid micelle
Irrotational flow of impressible ideal-fluid
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不可压缩理想流体的无旋运动
图 6—1 分析流体微团的平面运动