目次
第1章 流体の性質
第2章 流体の静力学
第3章 流体の動力学
第4章 管路内の流れ
第5章 抗力と揚力
第6章 次元解析および相似則
第2章 流体の静力学
第3章 流体の動力学
第4章 管路内の流れ
第5章 抗力と揚力
第6章 次元解析および相似則
内容説明
第1章 流体の性質
この章では，流体の基本的性質として， 圧縮性流体 c ompressible fluid や 非圧
縮性流体 incompressible fluid および 理想流体 i deal fluid の定義を理解する．ま
た， 国際単位系 International S ystem of u nits ; SI ）を確認したうえで 流体の性
質を表す各種物性値として， 密度 d ensity 単位体積当たりの重量 specific weight
比体積 specific volume 比重 specific gr avity 圧縮率 compressibility 体積弾
性係数 bulk modulus 粘度 viscosity および 動粘度 kinematic viscosity の定義と
算出方法を学ぶ．さらに， ニュートンの粘性法則 Newton’s law of v iscosity およ
び 表面張力 surface tension に関して，演習問題を通して学ぶことにする．
【Example 1-1 】
(1)Given the following units of measure, name the co rresponding physical property or state:
[ a ] :The mass per unit volume. SI kg/m 3 MKS: kgf ･ s 2 /m 4
[ b ] :The force from weight acting on a unit of volume. SI: N/m 3 MKS: kgf /m 3
[ c ] :This value represents the volume per unit mass. SIm 3 /kg MKS: m 3 /kgf
[ d ] :The ratio of fluid density to the maximum density of water at 101.325 k P a,3.98
[ e ] :The ratio of volumetric c ontraction to pressure increase
[ f ] :The ratio of shear stress to velocity gradient. SIN ･ s/m2 and Pa ･ s MKS: kgf ･ s/m 2
[g ] : The viscosity divided by the density. SI & MKS: m2 /
＊SI: International System of units
＊MKS: gravitational system of units (engineering system of units)
(2) (h)(h)––(k) Select the best (k) Select the best word to complete the following sentences:word to complete the following sentences:
An ‘ideal fluid’ is a hypothetical fluid that has zero (h) [viscosity, density]. Ideal s a hypothetical fluid that has zero (h) [viscosity, density]. Ideal fluids are only found in physics problems and do not exist in nature. In an ideal flow, fluids are only found in physics problems and do not exist in nature. In an ideal flow, shear force does not exist because it vanishes (h). Real fluids have (h) and these fluids shear force does not exist because it vanishes (h). Real fluids have (h) and these fluids obey obey the the Newtonian law: shear stress is directly proportional to shear strain.Newtonian law: shear stress is directly proportional to shear strain.
All fluids are (i) [compressible, incompressible] to some extent; that is, changes in pressure, or temperature cause changes in density. However, in many situations the pressure, or temperature cause changes in density. However, in many situations the changes in pressuchanges in pressure and temperature are sufficiently small that the changes in density re and temperature are sufficiently small that the changes in density are negligible (<5%). In this case the flow can be modeled as (j) [compressible, are negligible (<5%). In this case the flow can be modeled as (j) [compressible, incompressible].incompressible].
While all fluids are compressible, fluids are usually treated as (k) [compressible, incoincompressible] when the Mach number (the ratio of the mpressible] when the Mach number (the ratio of the flow velocityflow velocity to the speed of to the speed of sound) is less than 0.3.sound) is less than 0.3.
【SolutionSolution】
(1)
[a]:: densitydensity
[b]:: specific weightspecific weight
[c]:: specific volumespecific volume
[d]:: specific gravityspecific gravity
[e]:: compressibilitycompressibility
[f]:: viscosityviscosity
[g]:: kinematic viscositykinematic viscosity
(2)
(h):: viscosity viscosity
(i):: compressible compressible
(j):: incompressible incompressible
