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Momentum Transport(Summary)
动量传输(摘要)

2.Momentum Transport and Laminar Flow of Newtonian Fluids
2.牛顿流体的动量传输和层流

(1)Explanation of terms  (1)术语解释
Laminar flow:Flow is regarded as being the unidirectional movement of lamellae of fluid sliding over one another,with no macroscopic mixing or intermingling of the fluid in the radial direction.
层流:流动被视为流体层在相互滑动时的单向运动,且在径向上没有宏观混合或交融
Turbulent flow:In contrast to laminar flow,the fluid undergoes chaotic fluctuations,leading to intense mixing both in the axial direction and in the radial direction.
湍流:与层流相反,流体经历混乱的波动,导致在轴向和径向上都发生强烈的混合
Newton's law of viscosity:
牛顿粘度定律:
τ = μ d v x d y τ y x = μ d v x d y τ = μ d v x d y τ y x = μ d v x d y tau=mu(dv_(x))/(dy)quadtau_(yx)=-mu(dv_(x))/(dy)\tau=\mu \frac{d v_{x}}{d y} \quad \tau_{y x}=-\mu \frac{d v_{x}}{d y}
τ τ tau\tau-----viscous shear or momentum flux, Pa
τ τ tau\tau -----粘性剪切或动量通量,Pa

μ μ mu\mu-----dynamic viscosity,Pa's
μ μ mu\mu -----动态粘度,Pa·s


c.iviomentum Transport and Laminar Flow of Newtonian Fluids
c.牛顿流体的动量传输和层流

1)Explanation of terms  1)术语解释

Newton's law of viscosity: τ y x = μ d v x d y Momentum transport is driven by velocity gradient. τ y x = μ d v x d y  Momentum transport is driven by   velocity gradient. rarr"tau_(yx)=-mu(dv_(x))/(dy)"Longrightarrow{:[" Momentum transport is driven by "],[" velocity gradient."]:}\xrightarrow{\tau_{y x}=-\mu \frac{d v_{x}}{d y}} \Longrightarrow \begin{aligned} & \text { Momentum transport is driven by } \\ & \text { velocity gradient.}\end{aligned}
牛顿粘度定律: τ y x = μ d v x d y Momentum transport is driven by velocity gradient. τ y x = μ d v x d y  Momentum transport is driven by   velocity gradient. rarr"tau_(yx)=-mu(dv_(x))/(dy)"Longrightarrow{:[" Momentum transport is driven by "],[" velocity gradient."]:}\xrightarrow{\tau_{y x}=-\mu \frac{d v_{x}}{d y}} \Longrightarrow \begin{aligned} & \text { Momentum transport is driven by } \\ & \text { velocity gradient.}\end{aligned}
Reynolds number:  雷诺数:
Re = D × V 2 x 8 × ρ η = ( characteristic length ) × ( average velocity ) × ( density ) ( viscosity ) F g F η = ρ L 2 V x z 2 η V vzz L = ρ L V x z η = Re = Inertial force Viscous force Re = D × V 2 x 8 × ρ η = (  characteristic length  ) × (  average velocity  ) × (  density  ) (  viscosity  ) F g F η = ρ L 2 V x z 2 η V vzz L = ρ L V x z ¯ η = Re =  Inertial force   Viscous force  {:[Re=(D xxV_(2x8)xx rho)/(eta)],[=((" characteristic length ")xx(" average velocity ")xx(" density "))/((" viscosity "))],[(F_(g))/(F_(eta))=(rhoL^(2)V_(xz)^(2))/(etaV_(vzz)L)=(rho LV_( bar(xz)))/(eta)=Re=(" Inertial force ")/(" Viscous force ")]:}\begin{aligned} & \operatorname{Re}=\frac{D \times V_{2 x 8} \times \rho}{\eta} \\ & =\frac{(\text { characteristic length }) \times(\text { average velocity }) \times(\text { density })}{(\text { viscosity })} \\ & \frac{F_{\mathrm{g}}}{F_{\eta}}=\frac{\rho L^{2} V_{x z}^{2}}{\eta V_{\mathrm{vzz}} L}=\frac{\rho L V_{\overline{x z}}}{\eta}=\mathrm{Re}=\frac{\text { Inertial force }}{\text { Viscous force }} \end{aligned}
Viscosity of gases: μ = 2.6693 × 10 5 M T σ 2 Ω μ = 2.6693 × 10 5 M T σ 2 Ω mu=2.6693 xx10^(-5)(sqrt(MT))/(sigma^(2)Omega)\mu=2.6693 \times 10^{-5} \frac{\sqrt{M T}}{\sigma^{2} \Omega}
气体的粘度: μ = 2.6693 × 10 5 M T σ 2 Ω μ = 2.6693 × 10 5 M T σ 2 Ω mu=2.6693 xx10^(-5)(sqrt(MT))/(sigma^(2)Omega)\mu=2.6693 \times 10^{-5} \frac{\sqrt{M T}}{\sigma^{2} \Omega}
The viscosity of a gas is independent of the pressure of the gas and is a linear function of the square root of temperature.
气体的粘度与气体的压力无关,并且是温度平方根的线性函数

vivmentum Transport(Summary)
vivmentum Transport(摘要)

2.Momentum Transport and Laminar Flow of Newtonian Fluids
2.牛顿流体的动量传输和层流

(2)Analytical solutions  (2)解析解
Momentum balance based on a control volume(steady-state,constant density and viscosity)
基于控制体的动量平衡(稳态,恒定密度和粘度)

R Rate = = == Flux × × xx\times Area
R 速率 = = == 通量 × × xx\times 面积

\square Momentum includes convective momentum and viscous momentum
\square 动量包括对流动量和粘性动量

\square Forces include pressure and gravity
\square 力包括压力和重力

-Couette flow  -库埃特流
-Fluid flow between two parallel flat plates
-两个平行平板之间的流体流动

-Fluid flow down an inclined plane
-流体在倾斜平面上的流动

-Fluid flow in a cylindrical tube
-圆柱管中的流体流动

Momentum Transport(Summary)
动量传输(摘要)

2.Momentum Transport and Laminar Flow of Newtonian Fluids
2.牛顿流体的动量传输和层流

2)Analytical solutions  2)解析解
\square Couette flow   \square 库埃特流
v x = V Y y τ z = μ d v z d y } τ y x = μ V Y v x = V Y y τ z = μ d v z d y τ y x = μ V Y {:[v_(x)=(V)/(Y)y],[tau_(z)=-mu(dv_(z))/(dy)]}tau_(yx)=-mu(V)/(Y)\left.\begin{array}{l} v_{x}=\frac{V}{Y} y \\ \tau_{z}=-\mu \frac{d v_{z}}{d y} \end{array}\right\} \tau_{y x}=-\mu \frac{V}{Y}
Application:viscometer  应用:粘度计

L.Momentum Transport and Laminar Flow of Newtonian Fluids
L.牛顿流体的动量传输和层流

2)Analytical solutions  2)解析解
I Fluid flow between two parallel flat plates
我在两个平行平板之间的流体流动

v x = Δ P 2 μ L ( δ 2 y 2 ) τ y = μ d v x d y } τ y = Δ P L y v z = m = v x | , = Δ P 2 μ L δ 2 v x = 2 3 v x = Δ P 3 μ δ v x = Δ P 2 μ L δ 2 y 2 τ y = μ d v x d y τ y = Δ P L y      v z = m = v x , = Δ P 2 μ L δ 2 v x = 2 3 v x = Δ P 3 μ δ {:[v_(x)=(Delta P)/(2mu L)(delta^(2)-y^(2))],[tau_(y)=-mu(dv_(x))/(dy)]}{:[tau_(y)=(Delta P)/(L)y,v_(z=m)=v_(x)|_(,-oo)=(Delta P)/(2mu L)delta^(2)],[v_(x)=(2)/(3)v_(x)=(Delta P)/(3mu)delta]:}\left.\begin{array}{ll} v_{x}=\frac{\Delta P}{2 \mu L}\left(\delta^{2}-y^{2}\right) \\ \tau_{y}=-\mu \frac{d v_{x}}{d y} \end{array}\right\} \begin{array}{ll} \tau_{y}=\frac{\Delta P}{L} y & v_{z=m}=\left.v_{x}\right|_{,-\infty}=\frac{\Delta P}{2 \mu L} \delta^{2} \\ v_{x}=\frac{2}{3} v_{x}=\frac{\Delta P}{3 \mu} \delta \end{array}
c.iviumentum Transport and Laminar Flow of Newtonian Fluids
c.iviumentum 纽顿流体的运输和层流

2)Analytical solutions  2)解析解
-Fluid flow down an inclined plane
-流体在倾斜平面上的流动
v x = ρ g cos θ 2 μ ( δ 2 y 2 ) τ y x = μ d v x d y } τ y z = ρ g y cos θ v x = ρ g cos θ 2 μ δ 2 y 2 τ y x = μ d v x d y τ y z = ρ g y cos θ {:[v_(x)=(rho g cos theta)/(2mu)(delta^(2)-y^(2))],[tau_(yx)=-mu(dv_(x))/(dy)]}tau_(yz)=rho gy cos theta\left.\begin{array}{l} v_{x}=\frac{\rho g \cos \theta}{2 \mu}\left(\delta^{2}-y^{2}\right) \\ \tau_{y x}=-\mu \frac{d v_{x}}{d y} \end{array}\right\} \tau_{y z}=\rho g y \cos \theta
v x , m a x = v x | y 0 = ρ g cos θ 2 μ δ 2 v x , m a x = v x y 0 = ρ g cos θ 2 μ δ 2 v_(x,max)=v_(x)|_(y-0)=(rho g cos theta)/(2mu)delta^(2)v_{x, m a x}=\left.v_{x}\right|_{y-0}=\frac{\rho g \cos \theta}{2 \mu} \delta^{2}
v ¯ x = 2 3 v x , m a x = ρ g cos θ 3 μ δ 2 v ¯ x = 2 3 v x , m a x = ρ g cos θ 3 μ δ 2 bar(v)_(x)=(2)/(3)v_(x,max)=(rho g cos theta)/(3mu)delta^(2)\bar{v}_{x}=\frac{2}{3} v_{x, m a x}=\frac{\rho g \cos \theta}{3 \mu} \delta^{2}

Nomentum Transport(Summary)
Nomentum Transport(摘要)

2.Momentum Transport and Laminar Flow of Newtonian Fluids
2.牛顿流体的动量传输和层流

(2)Analytical solutions  (2)解析解
Fluid flow in a cylindrical tube(fully developed flow)
圆柱管中的流体流动(完全发展流动)

2)Analytical solutions  2)解析解

Couette
flow  库埃特流动

Fluid flow between two parallel flat plates
两个平行平板之间的流体流动
v x = V Y y τ μ = μ V Y v x , m x = V v z = 0 = Δ P 2 μ L δ 2 v ¯ x = 2 3 v x = v ¯ z = 1 2 v z = x ¯ ν x = Δ P 2 μ L ( δ 2 y 2 ) v z = ρ G cos θ 2 μ ( δ 2 y 2 ) v z = ( Δ P L ± ρ g cos θ ) R 2 r 2 4 μ τ y z = Δ P L y τ y z = ρ g y cos θ τ r = ( Δ P L ± ρ g cos θ ) r 2 v x = π = ρ g cos θ 2 μ δ 2 v z = = ( Δ P L ± ρ g cos θ ) R 2 4 μ v ¯ x = 2 3 v z = v ¯ z = 1 2 v z = v x = V Y y τ μ = μ V Y v x , m x = V v z = 0 = Δ P 2 μ L δ 2 v ¯ x = 2 3 v x = v ¯ z = 1 2 v z = x ¯ ν x = Δ P 2 μ L δ 2 y 2 v z = ρ G cos θ 2 μ δ 2 y 2 v z = Δ P L ± ρ g cos θ R 2 r 2 4 μ τ y z = Δ P L y τ y z = ρ g y cos θ τ r = Δ P L ± ρ g cos θ r 2 v x = π = ρ g cos θ 2 μ δ 2 v z = = Δ P L ± ρ g cos θ R 2 4 μ v ¯ x = 2 3 v z = v ¯ z = 1 2 v z = {:[v_(x)=(V)/(Y)y],[tau_(mu)=-mu(V)/(Y)],[v_(x,mx)=V quadv_(z=0)=(Delta P)/(2mu L)delta^(2)],[ bar(v)_(x)=(2)/(3)v_(x)=],[ bar(v)_(z)=(1)/(2)v_(z)= bar(x)],[nu_(x)=(Delta P)/(2mu L)(delta^(2)-y^(2))],[v_(z)=(rho G cos theta)/(2mu)(delta^(2)-y^(2))],[v_(z)=((Delta P)/(L)+-rho g cos theta)((R^(2)-r^(2))/(4mu))],[tau_(yz)=(Delta P)/(L)y],[tau_(yz)=rho gy cos theta],[tau_(r)=((Delta P)/(L)+-rho g cos theta)((r)/(2))],[v_(x=pi)=(rho g cos theta)/(2mu)delta^(2)],[v_(z=)=((Delta P)/(L)+-rho g cos theta)((R^(2))/(4mu))],[ bar(v)_(x)=(2)/(3)v_(z)=],[ bar(v)_(z)=(1)/(2)v_(z=)]:}\begin{aligned} & v_{x}=\frac{V}{Y} y \\ & \tau_{\mu}=-\mu \frac{V}{Y} \\ & v_{x, m x}=V \quad v_{z=0}=\frac{\Delta P}{2 \mu L} \delta^{2} \\ & \bar{v}_{\mathrm{x}}=\frac{2}{3} v_{\mathrm{x}}= \\ & \bar{v}_{\mathrm{z}}=\frac{1}{2} v_{\mathrm{z}}=\bar{x} \\ & \nu_{x}=\frac{\Delta P}{2 \mu L}\left(\delta^{2}-y^{2}\right) \\ & v_{z}=\frac{\rho G \cos \theta}{2 \mu}\left(\delta^{2}-y^{2}\right) \\ & v_{z}=\left(\frac{\Delta P}{L} \pm \rho g \cos \theta\right) \frac{R^{2}-r^{2}}{4 \mu} \\ & \tau_{y z}=\frac{\Delta P}{L} y \\ & \tau_{y z}=\rho g y \cos \theta \\ & \tau_{r}=\left(\frac{\Delta P}{L} \pm \rho g \cos \theta\right) \frac{r}{2} \\ & v_{x=\pi}=\frac{\rho g \cos \theta}{2 \mu} \delta^{2} \\ & v_{z=}=\left(\frac{\Delta P}{L} \pm \rho g \cos \theta\right) \frac{R^{2}}{4 \mu} \\ & \bar{v}_{x}=\frac{2}{3} v_{z}= \\ & \bar{v}_{z}=\frac{1}{2} v_{z=} \end{aligned}

Viomentum Transport(Summary)
Viomentum Transport(摘要)

3.Equations of Continuity and Conservation of Momentum and Fluid Flow Past Submerged Objects
3.连续性方程、动量守恒方程及流体流过沉没物体的流动
1)Explanation of terms  1)术语解释
Incompressible fluid:A fluid that has constant density( ρ = ρ = rho=\rho= const.)
不可压缩流体:一种具有恒定密度( ρ = ρ = rho=\rho= const.)的流体

Entry length at entrance to a pipe:The distance a flow travels after entering a pipe before the flow becomes fully developed.
管道入口的入口长度:流体进入管道后在流动完全发展之前流动的距离
2)Equations  2)方程式

Equation of continuily  连续性方程

ρ t + ( ρ v ) = 0 v = 0 ρ t + ( ρ v ) = 0 v = 0 (del rho)/(del t)+grad*(rhov)=0quad grad*v=0\frac{\partial \rho}{\partial t}+\nabla \cdot(\rho \mathrm{v})=0 \quad \nabla \cdot \mathrm{v}=0
Equation of momentum conservation
动量守恒方程
t ρ v = τ ¯ ρ v v P + ρ g t ρ v = τ ¯ ¯ ρ v v P + ρ g (del)/(del t)rhov=-grad* bar(bar(tau))-grad*rhovv-grad P+rhog\frac{\partial}{\partial t} \rho \mathbf{v}=-\nabla \cdot \overline{\bar{\tau}}-\nabla \cdot \rho \mathbf{v} \mathbf{v}-\nabla P+\rho \mathbf{g}
\square Accumulation   \square 积累
\square Viscous   \square 粘性
-Convective  -对流
\square Surface force   \square 表面力
\square Body force   \square 体力
3.Equations of Continuity and Conservation of Momentum and Fluid Flow Past Submerged Objects
3.连续性方程、动量守恒方程及流体流过沉没物体的流动
2)Equations  2)方程式
ρ D v D t = η 2 v P + ρ g { ρ D v z D t = η ( 2 v z x 2 + σ ^ 2 v z y 2 + σ ^ 2 v z σ ^ 2 ) σ ^ P x + ρ g z ρ D v y D t = η ( σ ^ 2 v y x 2 + σ ^ 2 v y y 2 + σ ^ 2 v y a ^ 2 ) σ ^ P ^ y + ρ g y ρ D v z D t = η ( 2 v z x ^ x 2 + σ ^ 2 v z y 2 + σ ^ 2 v z z ^ 2 ) ^ P c ^ z + ρ g ρ D v D t = η 2 v P + ρ g ρ D v z D t = η 2 v z x 2 + σ ^ 2 v z y 2 + σ ^ 2 v z σ ^ 2 σ ^ P x + ρ g z ρ D v y D t = η σ ^ 2 v y x 2 + σ ^ 2 v y y 2 + σ ^ 2 v y a ^ 2 σ ^ P ^ y + ρ g y ρ D v z D t = η 2 v z x ^ x 2 + σ ^ 2 v z y 2 + σ ^ 2 v z z ^ 2 ^ P c ^ z + ρ g rho(Dv)/(Dt)=etagrad^(2)v-grad P+rhog{[rho(Dv_(z))/(Dt)=eta((del^(2)v_(z))/(delx^(2))+( hat(sigma)^(2)v_(z))/(dely^(2))+( hat(sigma)^(2)v_(z))/( hat(sigma)^(2)))-(( hat(sigma))P)/(del x)+rhog_(z)],[rho(Dv_(y))/(Dt)=eta(( hat(sigma)^(2)v_(y))/(delx^(2))+( hat(sigma)^(2)v_(y))/(dely^(2))+( hat(sigma)^(2)v_(y))/( hat(a)^(2)))-(( hat(sigma))P)/(( hat(del))y)+rhog_(y)],[rho(Dv_(z))/(Dt)=eta((del^(2)v_(z))/(( hat(del x))x^(2))+( hat(sigma)^(2)v_(z))/(dely^(2))+( hat(sigma)^(2)v_(z))/( hat(z)^(2)))-(( hat(del))P)/(( hat(c))z)+rho g]:}\rho \frac{D \mathbf{v}}{D t}=\eta \nabla^{2} \mathbf{v}-\nabla P+\rho \mathbf{g}\left\{\begin{array}{l} \rho \frac{D v_{z}}{D t}=\eta\left(\frac{\partial^{2} v_{z}}{\partial x^{2}}+\frac{\hat{\sigma}^{2} v_{z}}{\partial y^{2}}+\frac{\hat{\sigma}^{2} v_{z}}{\hat{\sigma}^{2}}\right)-\frac{\hat{\sigma} P}{\partial x}+\rho g_{z} \\ \rho \frac{D v_{y}}{D t}=\eta\left(\frac{\hat{\sigma}^{2} v_{y}}{\partial x^{2}}+\frac{\hat{\sigma}^{2} v_{y}}{\partial y^{2}}+\frac{\hat{\sigma}^{2} v_{y}}{\hat{a}^{2}}\right)-\frac{\hat{\sigma} P}{\hat{\partial} y}+\rho g_{y} \\ \rho \frac{D v_{z}}{D t}=\eta\left(\frac{\partial^{2} v_{z}}{\hat{\partial x} x^{2}}+\frac{\hat{\sigma}^{2} v_{z}}{\partial y^{2}}+\frac{\hat{\sigma}^{2} v_{z}}{\hat{z}^{2}}\right)-\frac{\hat{\partial} P}{\hat{c} z}+\rho g \end{array}\right.
Prandtl boundary layer equation:
普朗特边界层方程:
^ v x x + ^ v y y ^ = 0 v x = v y = 0 ( a y = 0 v x ^ v z x + v y v x y y = v ^ 2 v x y 2 v x = 0.99 v x ( a y = δ ^ v x x + ^ v y y ^ = 0      v x = v y = 0      ( a y = 0 v x ^ v z x + v y v x y y = v ^ 2 v x y 2      v x = 0.99 v x      ( a y = δ {:[(( hat(del))v_(x))/(del x)+(( hat(del))v_(y))/(( hat(del y)))=0,v_(x)=v_(y)=0,(ay=0],[v_(x)(( hat(del))v_(z))/(del x)+v_(y)(delv_(x))/((del y)/(del y)=v( hat(del)^(2)v_(x))/(dely^(2))),v_(x)=0.99v_(x),(ay=delta]:}\begin{array}{lll} \frac{\hat{\partial} v_{x}}{\partial x}+\frac{\hat{\partial} v_{y}}{\hat{\partial y}}=0 & v_{x}=v_{y}=0 & (a y=0 \\ v_{x} \frac{\hat{\partial} v_{z}}{\partial x}+v_{y} \frac{\partial v_{x}}{\frac{\partial y}{\partial y}=v \frac{\hat{\partial}^{2} v_{x}}{\partial y^{2}}} & v_{x}=0.99 v_{x} & (a y=\delta \end{array}
3.Equations of Continuity and Conservation of Momentum and Fluid Flow Past Submerged Objects
3.连续性方程、动量守恒方程及流体流过沉没物体的流动
2)Equations  2)方程式

Blasius's exact solution:
Blasius 的精确解:

δ x = 5.0 Re x δ x = 5.0 Re x (delta )/(x)=(5.0)/(sqrt(Re_(x)))\frac{\delta}{x}=\frac{5.0}{\sqrt{\mathrm{Re}_{x}}}
C x = 0.664 Re x C x = 0.664 Re x C_(x)=(0.664)/(sqrt(Re_(x)))C_{x}=\frac{0.664}{\sqrt{\mathrm{Re}_{\mathrm{x}}}}
C ¯ L = 1.328 Re L C ¯ L = 1.328 Re L bar(C)_(L)=(1.328)/(sqrt(Re_(L)))\bar{C}_{L}=\frac{1.328}{\sqrt{\operatorname{Re}_{L}}}
Approximate solution:  近似解:
δ x = 4.641 Re x δ x = 4.641 Re x (delta )/(x)=(4.641)/(sqrt(Re_(x)))\frac{\delta}{x}=\frac{4.641}{\sqrt{\mathrm{Re}_{x}}}
C x = 0.646 Re x C x = 0.646 Re x C_(x)=(0.646)/(sqrt(Re_(x)))C_{x}=\frac{0.646}{\sqrt{\operatorname{Re}_{x}}}
C ¯ L = 1.292 Re L C ¯ L = 1.292 Re L bar(C)_(L)=(1.292)/(sqrt(Re_(L)))\bar{C}_{L}=\frac{1.292}{\sqrt{\mathrm{Re}_{L}}}
v x = 3 2 v x δ y 1 2 v x δ 3 y 3 τ xall = τ y x | y = 0 = μ v x y | y = 0 v x y | y = 0 = 0 F = C ¯ L 1 2 ρ v x 2 W L v x = 3 2 v x δ y 1 2 v x δ 3 y 3 τ xall = τ y x y = 0 = μ v x y y = 0 v x y y = 0 = 0 F = C ¯ L 1 2 ρ v x 2 W L {:[v_(x)=(3)/(2)(v_(x))/(delta)y-(1)/(2)(v_(x))/(delta^(3))y^(3)],[tau_(xall)=-tau_(yx)|_(y=0)= mu(delv_(x))/(del y)|_(y=0)],[(delv_(x))/(del y)|_(y=0)=0],[F= bar(C)_(L)(1)/(2)rhov_(x)^(2)WL]:}\begin{aligned} & v_{x}=\frac{3}{2} \frac{v_{x}}{\delta} y-\frac{1}{2} \frac{v_{x}}{\delta^{3}} y^{3} \\ & \tau_{\mathrm{xall}}=-\left.\tau_{y x}\right|_{y=0}=\left.\mu \frac{\partial v_{x}}{\partial y}\right|_{y=0} \\ & \left.\frac{\partial v_{x}}{\partial y}\right|_{y=0}=0 \\ & F=\bar{C}_{L} \frac{1}{2} \rho v_{x}^{2} W L \end{aligned}

Stokes's law:  斯托克斯定律:

4 3 π R 3 ( ρ 2 ρ ) g = 6 π R μ ν t Re = ρ D v t μ < 0.1 4 3 π R 3 ρ 2 ρ g = 6 π R μ ν t Re = ρ D v t μ < 0.1 (4)/(3)piR^(3)(rho_(2)-rho)g=6pi R munu_(t)quadRe=(rho Dv_(t))/(mu) < 0.1\frac{4}{3} \pi R^{3}\left(\rho_{2}-\rho\right) g=6 \pi R \mu \nu_{\mathrm{t}} \quad \mathrm{Re}=\frac{\rho D v_{\mathrm{t}}}{\mu}<0.1

4.Turbulent Flow  4.湍流

(1)Friction factor(flow within pipes)
(1)摩擦因子(管道内流动)
Δ P = 1 2 p v ¯ 2 4 L D Δ P = 1 2 p v ¯ 2 4 L D Delta P=int(1)/(2)p bar(v)^(-2)(4L)/(D)\Delta P=\int \frac{1}{2} p \bar{v}^{-2} \frac{4 L}{D}
v ¯ v max = 0.817 v ¯ v max = 0.817 (( bar(v)))/(v_(max))=0.817\frac{\bar{v}}{v_{\max }}=0.817
Smooth-walled circular pipes:
光滑壁圆形管:
As for laminar flows ( Re < 2100 ) f = 16 Re ( Re < 2100 ) f = 16 Re (Re < 2100)quad f=(16)/(Re)(\operatorname{Re}<2100) \quad f=\frac{16}{\mathrm{Re}}
关于层流 ( Re < 2100 ) f = 16 Re ( Re < 2100 ) f = 16 Re (Re < 2100)quad f=(16)/(Re)(\operatorname{Re}<2100) \quad f=\frac{16}{\mathrm{Re}}

Blasius one-seventh power law
布拉修斯一七次方定律
As for turbulent flows ( 2100 < Re < 10 5 ) f = 0.0791 Re 025 2100 < Re < 10 5 f = 0.0791 Re 025 (2100 < Re < 10^(5))quad f=(0.0791)/(Re^(025))\left(2100<\operatorname{Re}<10^{5}\right) \quad f=\frac{0.0791}{\operatorname{Re}^{025}}
关于湍流 ( 2100 < Re < 10 5 ) f = 0.0791 Re 025 2100 < Re < 10 5 f = 0.0791 Re 025 (2100 < Re < 10^(5))quad f=(0.0791)/(Re^(025))\left(2100<\operatorname{Re}<10^{5}\right) \quad f=\frac{0.0791}{\operatorname{Re}^{025}}
As for turbulent flows ( 3 × 10 3 < Re < 10 8 ) 1 f = 4 log ( 2 Re f ) 1.6 3 × 10 3 < Re < 10 8 1 f = 4 log ( 2 Re f ) 1.6 (3xx10^(3) < Re < 10^(8))(1)/(sqrtf)=4log(2Resqrtf)-1.6\left(3 \times 10^{3}<\operatorname{Re}<10^{8}\right) \frac{1}{\sqrt{f}}=4 \log (2 \operatorname{Re} \sqrt{f})-1.6
关于湍流 ( 3 × 10 3 < Re < 10 8 ) 1 f = 4 log ( 2 Re f ) 1.6 3 × 10 3 < Re < 10 8 1 f = 4 log ( 2 Re f ) 1.6 (3xx10^(3) < Re < 10^(8))(1)/(sqrtf)=4log(2Resqrtf)-1.6\left(3 \times 10^{3}<\operatorname{Re}<10^{8}\right) \frac{1}{\sqrt{f}}=4 \log (2 \operatorname{Re} \sqrt{f})-1.6

Rough-walled circular pipes:
粗壁圆形管道:

As for laminar flows ( Re < 2100 ) : f = 16 Re ( Re < 2100 ) : f = 16 Re (Re < 2100):quad f=(16 )/(Re)(\operatorname{Re}<2100): \quad f=\frac{16}{\operatorname{Re}}
关于层流 ( Re < 2100 ) : f = 16 Re ( Re < 2100 ) : f = 16 Re (Re < 2100):quad f=(16 )/(Re)(\operatorname{Re}<2100): \quad f=\frac{16}{\operatorname{Re}}

As for turbulent flows ( Re > 2100 ) : 1 f = 4 log [ 1.26 Re f + ε 3.7 D ] ( Re > 2100 ) : 1 f = 4 log 1.26 Re f + ε 3.7 D (Re > 2100):(1)/(sqrtf)=-4log[(1.26)/(Resqrtf)+(epsi)/(3.7 D)](\operatorname{Re}>2100): \frac{1}{\sqrt{f}}=-4 \log \left[\frac{1.26}{\operatorname{Re} \sqrt{f}}+\frac{\varepsilon}{3.7 D}\right] or 1 f = 3.6 log [ 6.9 Re + ( ε 3.7 D ) LII ] 2 : 1 f = 3.6 log 6.9 Re + ε 3.7 D LII 2 : (1)/(sqrtf)=-3.6 log [(6.9 )/(Re)+((epsi)/(3.7 D))^(LII)]_(2:)\frac{1}{\sqrt{f}}=-3.6 \log \left[\frac{6.9}{\operatorname{Re}}+\left(\frac{\varepsilon}{3.7 D}\right)^{\mathrm{LII}}\right]_{2:}
至于湍流 ( Re > 2100 ) : 1 f = 4 log [ 1.26 Re f + ε 3.7 D ] ( Re > 2100 ) : 1 f = 4 log 1.26 Re f + ε 3.7 D (Re > 2100):(1)/(sqrtf)=-4log[(1.26)/(Resqrtf)+(epsi)/(3.7 D)](\operatorname{Re}>2100): \frac{1}{\sqrt{f}}=-4 \log \left[\frac{1.26}{\operatorname{Re} \sqrt{f}}+\frac{\varepsilon}{3.7 D}\right] 1 f = 3.6 log [ 6.9 Re + ( ε 3.7 D ) LII ] 2 : 1 f = 3.6 log 6.9 Re + ε 3.7 D LII 2 : (1)/(sqrtf)=-3.6 log [(6.9 )/(Re)+((epsi)/(3.7 D))^(LII)]_(2:)\frac{1}{\sqrt{f}}=-3.6 \log \left[\frac{6.9}{\operatorname{Re}}+\left(\frac{\varepsilon}{3.7 D}\right)^{\mathrm{LII}}\right]_{2:}

Iviomentum Transport(Summary)
Iviomentum Transport(摘要)

4.Turbulent Flow  4.湍流
2)Friction factor(flow over flat plates)
2)摩擦因子(平板流动)

3)Friction factor(flow across spheres/cylinders)
3)摩擦因子(流经球体/圆柱体)
F = f A 1 2 ρ v 2 2 = f π 2 2 1 2 ρ t 2 F = f A 1 2 ρ v 2 2 = f π 2 2 1 2 ρ t 2 F=fA(1)/(2)rhov_(2)^(2)=fpi_(2)^(2)(1)/(2)rho_(t)^(2)F=f A \frac{1}{2} \rho v_{2}^{2}=f \pi_{2}^{2} \frac{1}{2} \rho_{t}^{2}
f = 24 Re f = 24 Re f=(24 )/(Re)f=\frac{24}{\operatorname{Re}}
f = 18.5 Re 0.6 f = 18.5 Re 0.6 f=(18.5)/(Re^(0.6))f=\frac{18.5}{\operatorname{Re}^{0.6}}
f = 0.44 f = 0.44 f=0.44f=0.44

Momentum Transport(Summary)
动量传输(摘要)

5.Mechanical Energy Balance and Its Application to Fluid Flow
5.机械能平衡及其在流体流动中的应用

"1)Modified Bernoulli equation
1)修正的伯努利方程
{ P 1 ρ + 1 2 β v ¯ 1 2 + g z 1 + α ^ E f = P 2 ρ + 1 2 β v ¯ 2 2 + g z 2 β = { 0.5 Laminar 1 Turbulent P 1 ρ + 1 2 β v ¯ 1 2 + g z 1 + α ^ E f = P 2 ρ + 1 2 β v ¯ 2 2 + g z 2 β = 0.5  Laminar  1  Turbulent  {[(P_(1))/(rho)+(1)/(2beta) bar(v)_(1)^(2)+gz_(1)+ hat(alpha)-E_(f)=(P_(2))/(rho)+(1)/(2beta) bar(v)_(2)^(2)+gz_(2)],[beta={[0.5," Laminar "],[1," Turbulent "]:}]:}\left\{\begin{array}{l} \frac{P_{1}}{\rho}+\frac{1}{2 \beta} \bar{v}_{1}^{2}+g z_{1}+\hat{\alpha}-E_{\mathrm{f}}=\frac{P_{2}}{\rho}+\frac{1}{2 \beta} \bar{v}_{2}^{2}+g z_{2} \\ \beta= \begin{cases}0.5 & \text { Laminar } \\ 1 & \text { Turbulent }\end{cases} \end{array}\right.
Friction loss { wall shear E f = f 4 L D 1 2 v ¯ 2 bends and fittings E f = f 4 L e D 1 2 v ¯ 2 changes in radius E f = e f 1 2 v ¯ s 2  wall shear       E f = f 4 L D 1 2 v ¯ 2  bends and fittings       E f = f 4 L e D 1 2 v ¯ 2  changes in radius       E f = e f 1 2 v ¯ s 2 {[" wall shear ",E_(f)=f((4L)/(D))(1)/(2) bar(v)^(2)],[" bends and fittings ",E_(f)=f((4L_(e))/(D))(1)/(2) bar(v)^(2)],[" changes in radius ",E_(f)=e_(f)(1)/(2) bar(v)_(s)^(2)]:}\begin{cases}\text { wall shear } & E_{\mathrm{f}}=f \frac{4 L}{D} \frac{1}{2} \bar{v}^{2} \\ \text { bends and fittings } & E_{\mathrm{f}}=f \frac{4 L_{\mathrm{e}}}{D} \frac{1}{2} \bar{v}^{2} \\ \text { changes in radius } & E_{\mathrm{f}}=e_{\mathrm{f}} \frac{1}{2} \bar{v}_{\mathrm{s}}^{2}\end{cases}  摩擦损失 { wall shear E f = f 4 L D 1 2 v ¯ 2 bends and fittings E f = f 4 L e D 1 2 v ¯ 2 changes in radius E f = e f 1 2 v ¯ s 2  wall shear       E f = f 4 L D 1 2 v ¯ 2  bends and fittings       E f = f 4 L e D 1 2 v ¯ 2  changes in radius       E f = e f 1 2 v ¯ s 2 {[" wall shear ",E_(f)=f((4L)/(D))(1)/(2) bar(v)^(2)],[" bends and fittings ",E_(f)=f((4L_(e))/(D))(1)/(2) bar(v)^(2)],[" changes in radius ",E_(f)=e_(f)(1)/(2) bar(v)_(s)^(2)]:}\begin{cases}\text { wall shear } & E_{\mathrm{f}}=f \frac{4 L}{D} \frac{1}{2} \bar{v}^{2} \\ \text { bends and fittings } & E_{\mathrm{f}}=f \frac{4 L_{\mathrm{e}}}{D} \frac{1}{2} \bar{v}^{2} \\ \text { changes in radius } & E_{\mathrm{f}}=e_{\mathrm{f}} \frac{1}{2} \bar{v}_{\mathrm{s}}^{2}\end{cases}
set 限制解除