fluid_dynamics_pressure

fluid_dynamics_pressure

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% Author: Izaak Neutelings (November 2020)
\documentclass[border=3pt,tikz]{standalone}
\usepackage{siunitx}
\usepackage{physics}
\usepackage{tikz}
\usepackage[outline]{contour} % glow around text
\usetikzlibrary{patterns,decorations.pathmorphing}
\usetikzlibrary{arrows.meta}
\tikzset{>=latex}
\contourlength{1.1pt}

\colorlet{mydarkblue}{blue!50!black}
\colorlet{myblue}{blue!30}
\colorlet{myred}{red!65!black}
\colorlet{vcol}{green!45!black}
\colorlet{watercol}{blue!80!cyan!10!white}
\colorlet{darkwatercol}{blue!80!cyan!20!white}
\colorlet{metalcol}{blue!40!black!10!white}
\tikzstyle{force}=[->,myred,very thick,line cap=round]
\tikzstyle{vvec}=[->,very thick,vcol,line cap=round]
\tikzstyle{piston}=[blue!50!black,top color=blue!30,bottom color=blue!50,middle color=blue!20,shading angle=0]
\tikzstyle{water}=[draw=mydarkblue,top color=watercol!90,bottom color=watercol!90!black,shading angle=5]
\tikzstyle{vertical water}=[water,
  top color=watercol!90!black!90,bottom color=watercol!90!black!90,middle color=watercol!80,shading angle=90]
\tikzstyle{dark water}=[draw=mydarkblue,top color=darkwatercol,bottom color=darkwatercol!80!black,shading angle=5]
\tikzstyle{metal}=[draw=metalcol!20!black,top color=metalcol,bottom color=metalcol!90!black,shading angle=10]
\tikzstyle{width}=[{Latex[length=3,width=3]}-{Latex[length=3,width=3]}]
\def\tick#1#2{\draw[thick] (#1)++(#2:0.1) --++ (#2-180:0.2)}

\begin{document}


% PRESSURE
\begin{tikzpicture}[x={(1cm,0)},y={(0.65cm,0.6cm)},z={(0,1cm)}]
  \def\L{1.6} % cube side
  \def\P{0.8} % pressure size
  \draw[dark water] (0,0,0) -- (\L,0,0) -- (\L,\L,0) -- ( 0,\L,0) -- cycle;
  \draw[force] (0.5*\L,0.5*\L,1.01*\P) node[right=2,above=3] {$P$} --++ (0,0,-\P);
  \foreach \x/\y in {0.5/0.5,0.5/0.2,0.2/0.5,0.5/0.8,0.8/0.5,0.8/0.8,0.2/0.8,0.2/0.2,0.8/0.2}{
    \draw[force] (\x*\L,\y*\L,1.01*\P) --++ (0,0,-\P);
  }
\end{tikzpicture}


% PRESSURE DIRECTIONS - Pascal's principle
\begin{tikzpicture}[x={(1cm,0)},y={(0.5cm,0.4cm)},z={(0,1cm)}]
  \def\L{0.8} % cube side
  \def\P{0.6} % pressure size
  \draw[force] (\L/2,\L/2,-1.1*\P) node[below] {$P$} --++ (0,0,\P);
  \draw[force] (-1.1*\P,\L/2,\L/2) node[left] {$P$} --++ ( \P,0,0);
  \draw[force] (\L/2,\L+1.5*\P,\L/2) node[above right=-2] {$P$} --++ (0,-1.4*\P,0);
  \draw[dark water,rounded corners=0.1] (\L,0, 0) -- (\L,0,\L) -- (\L,\L,\L) -- (\L,\L, 0) -- cycle;
  \draw[dark water,rounded corners=0.1] ( 0,0, 0) -- ( 0,0,\L) -- (\L, 0,\L) -- (\L, 0, 0) -- cycle;
  \draw[dark water,rounded corners=0.1] ( 0,0,\L) -- (\L,0,\L) -- (\L,\L,\L) -- ( 0,\L,\L) -- cycle;
  \draw[force] (\L/2,\L/2,\L+1.05*\P) node[above] {$P$} --++ (0,0,-\P);
  \draw[force] (\L+1.05*\P,\L/2,\L/2) node[right] {$P$} --++ (-\P,0,0);
  \draw[force] (\L/2,-1.4*\P,\L/2) node[below left=-3] {$P$} --++ (0,1.4*\P,0);
\end{tikzpicture}


% WATER COLUMN WEIGHT
\begin{tikzpicture}
  \def\Rx{1.0}      % tank horizontal radius
  \def\Ry{0.3}      % tank vertical radius
  \def\H{3}         % height tank
  \def\h{0.94*\H}   % height water
  \def\y{0.40*\H}   % vertical position piece
  \def\F{0.45*\h}   % force
  
  % WATER
  \draw[vertical water]
    (-\Rx,\h) -- (-\Rx,0) arc (180:360:{\Rx} and {\Ry}) -- (\Rx,\h);
  \draw[water]
    (0,\h) ellipse ({\Rx} and {\Ry});
  
  % CONTAINER
  \draw[thick]
    (-\Rx,\H) -- (-\Rx,0) arc (180:360:{\Rx} and {\Ry}) -- (\Rx,\H);
  \draw[thick]
    (0,\H) ellipse ({\Rx} and {\Ry});
  
  % LABELS
  \draw[force] (-0.1*\Rx,\h/2) --++ (0,-0.3*\F) node[midway,left] {$mg$};
  \draw[force] (0.1*\Rx,-0.8*\Ry) --++ (0,\F) node[midway,right] {$\vb{F}_\mathrm{N}$};
  \draw[force] (0.0*\Rx,\h-1.2*\Ry) --++ (0,-0.7*\F) node[midway,right] {$\vb{F}_\mathrm{atm}$};
  \node[right] at (1.1*\Rx,\H) {$P_0=P_\mathrm{atm}$}; %{\contour{watercol}{$P_\mathrm{atm}$}};
  \node[right] at (1.1*\Rx,0) {$P$};
  \node[above=-5] at (0,\h) {$A$};
  \draw[<->] (-1.2*\Rx,0) --++ (0,\h) node[midway,fill=white,inner sep=1] {$h$};
  
\end{tikzpicture}


% WATER COLUMN WEIGHT
\begin{tikzpicture}
  \def\Rx{1.2}      % tank horizontal radius
  \def\Ry{0.5}      % tank vertical radius
  \def\rx{0.22*\Rx} % column horizontal radius
  \def\ry{0.22*\Ry} % column vertical radius
  \def\H{3}         % height tank
  \def\h{0.94*\H}   % height water
  \def\y{0.40*\H}   % vertical position piece
  \def\dy{0.10*\H}  % height piece
  
  % WATER
  \draw[vertical water]
    (-\Rx,\h) -- (-\Rx,0) arc (180:360:{\Rx} and {\Ry}) -- (\Rx,\h);
  \draw[water]
    (0,\h) ellipse ({\Rx} and {\Ry});
  
  % COLUMN + PIECE
  \draw[dark water]
    (-\rx,\y) -- (-\rx,\y-\dy) arc (180:360:{\rx} and {\ry}) -- (\rx,\y);
  \draw[dark water]
    (0,\y) ellipse ({\rx} and {\ry});
  \draw[dark water,opacity=0.50,draw=none] % column
    (-\rx,\h) -- (-\rx,\y) arc (180:360:{\rx} and {\ry}) -- (\rx,\h) arc(360:180:{\rx} and {\ry}) -- cycle;
  \draw[blue!20!black,dashed,very thin,opacity=0.50] (-\rx,\y) -- (-\rx,\h) (\rx,\y) -- (\rx,\h);
  \draw[dark water,opacity=0.50] % top column
    (0,\h) ellipse ({\rx} and {\ry});
  \draw[blue!30!black]
    (0,\h) ellipse ({\Rx} and {\Ry});
  
  % CONTAINER
  \draw[thick]
    (-\Rx,\H) -- (-\Rx,0) arc (180:360:{\Rx} and {\Ry}) -- (\Rx,\H);
  \draw[thick]
    (0,\H) ellipse ({\Rx} and {\Ry});
  
  % LABELS
  \node at ({-0.44*(\Rx+\rx)},1.03*\h) {$P_\mathrm{atm}$}; %{\contour{watercol}{$P_\mathrm{atm}$}};
  \node at ({-0.40*(\Rx+\rx)},{\y-0.5*\dy}) {$P$};
  \node[above=-2] at (0,\y+\ry) {$A$};
  \draw[<->] (1.2*\Rx,\y) --++ (0,\h-\y) node[midway,fill=white,inner sep=1] {$h$};
  
\end{tikzpicture}


% PRESSURE HEIGTH DIFFERENCE
\begin{tikzpicture}
  \def\Rx{1.2}      % tank horizontal radius
  \def\Ry{0.2}      % tank vertical radius
  \def\H{3}         % height tank
  \def\h{0.94*\H}   % height water
  \def\ya{0.65*\h}  % vertical position A
  \def\yb{0.20*\h}  % vertical position B
  
  % WATER
  \draw[vertical water]
    (-\Rx,\h) -- (-\Rx,0) arc (180:360:{\Rx} and {\Ry}) -- (\Rx,\h);
  \draw[water]
    (0,\h) ellipse ({\Rx} and {\Ry});
  \draw[thick]
    (-\Rx,\H) -- (-\Rx,0) arc (180:360:{\Rx} and {\Ry}) -- (\Rx,\H)
    (0,\H) ellipse ({\Rx} and {\Ry});
  
  % LABELS
  %\node at ({-0.44*(\Rx+\rx)},1.04*\h) {$P_\mathrm{atm}$}; %{\contour{watercol}{$P_\mathrm{atm}$}};
  %\node at ({-0.40*(\Rx+\rx)},{\y-0.5*\dy}) {$P$};
  \draw[blue!30!black,dashed] (-1.3*\Rx,\ya) --++ (2.6*\Rx,0);
  \draw[blue!30!black,dashed] (-1.3*\Rx,\yb) --++ (2.6*\Rx,0);
  \draw[<->] (-1.2*\Rx,\yb) --++ (0,\ya-\yb) node[midway,fill=white,inner sep=1] {$h$};
  \node at (0,\ya) {\contour{watercol!80}{$P_1$}};
  \node at (0,\yb) {\contour{watercol!80}{$P_2$}};
  
  % AXIS
  \begin{scope}[shift={(1.3*\Rx,0)}]
    \draw[->,thick] (-0.03*\h,\h) --++ (1.2*\h,0) node[right=-1] {$P$\,[Pa]};
    \draw[->,thick] (0,1.03*\h) --++ (0,-1.2*\h) node[above=2,right] {$y$\,[m]};
    \draw[blue!30!black,dashed] (0,\ya) -| ({\H-\H/(\h)*\ya},\h);
    \draw[blue!30!black,dashed] (0,\yb) -| ({\H-\H/(\h)*\yb},\h);
    \tick{0,\ya}{180} node[right=0,fill=white,inner sep=1] {$y_1$};
    \tick{0,\yb}{180} node[right=0,fill=white,inner sep=1] {$y_2$};
    %\tick{0,\h}{180}; %node[above=2,right=-1] {$h$};
    \tick{0,\h}{-90} node[right=2,above=-1,scale=0.9] {$P_\mathrm{atm}$};
    \tick{{\H-\H/(\h)*\ya},\h}{-90} node[above=-1,scale=0.9] {$P_1$};
    \tick{{\H-\H/(\h)*\yb},\h}{-90} node[above=-1,scale=0.9] {$P_2$};
    %\tick{0.8*\H,0}{90} node[below=-1,scale=0.9] {$P_\mathrm{atm}+\rho g H$};
    \draw[blue!60!black,very thick] (0,\h) -- (\H,0);
  \end{scope}
  
\end{tikzpicture}


% PRESSURE HEIGTH DIFFERENCE
\begin{tikzpicture}
  \def\Rx{1.2}      % tank horizontal radius
  \def\Ry{0.2}      % tank vertical radius
  \def\H{3}         % height tank
  \def\h{0.94*\H}   % height water
  \def\ya{0.65*\h}  % vertical position A
  \def\yb{0.20*\h}  % vertical position B
  
  % WATER
  \draw[vertical water]
    (-\Rx,\h) -- (-\Rx,0) arc (180:360:{\Rx} and {\Ry}) -- (\Rx,\h);
  \draw[water]
    (0,\h) ellipse ({\Rx} and {\Ry});
  \draw[thick]
    (-\Rx,\H) -- (-\Rx,0) arc (180:360:{\Rx} and {\Ry}) -- (\Rx,\H)
    (0,\H) ellipse ({\Rx} and {\Ry});
  
  % LABELS
  %\node at ({-0.44*(\Rx+\rx)},1.04*\h) {$P_\mathrm{atm}$}; %{\contour{watercol}{$P_\mathrm{atm}$}};
  %\node at ({-0.40*(\Rx+\rx)},{\y-0.5*\dy}) {$P$};
  \draw[blue!30!black,dashed] (-1.3*\Rx,\ya) --++ (2.6*\Rx,0);
  \draw[blue!30!black,dashed] (-1.3*\Rx,\yb) --++ (2.6*\Rx,0);
  \draw[<->] (-1.2*\Rx,\yb) --++ (0,\ya-\yb) node[midway,fill=white,inner sep=1] {$h$};
  \node at (0,\ya) {\contour{watercol!80}{$P_1$}};
  \node at (0,\yb) {\contour{watercol!80}{$P_2$}};
  
  % AXIS
  \begin{scope}[shift={(1.25*\Rx,0)}]
    \draw[->,thick] (-0.05*\H,0) --++ (1.2*\H,0) node[right=-1] {$P$\,[Pa]};
    \draw[->,thick] (0,-0.05*\H) --++ (0,1.2*\H) node[right] {$y$\,[m]};
    \draw[blue!30!black,dashed] (0,\ya) -| ({\H-\H/(\h)*\ya},0);
    \draw[blue!30!black,dashed] (0,\yb) -| ({\H-\H/(\h)*\yb},0);
    \tick{0,\ya}{180} node[right=0,fill=white,inner sep=1] {$y_1$};
    \tick{0,\yb}{180} node[right=0,fill=white,inner sep=1] {$y_2$};
    %\tick{0,\h}{180}; %node[above=2,right=-1] {$h$};
    \tick{0,0}{90} node[below=-1,scale=0.9] {$P_\mathrm{atm}$};
    \tick{{\H-\H/(\h)*\ya},0}{90} node[below=-1,scale=0.9] {$P_1$};
    \tick{{\H-\H/(\h)*\yb},0}{90} node[below=-1,scale=0.9] {$P_2$};
    %\tick{0.8*\H,0}{90} node[below=-1,scale=0.9] {$P_\mathrm{atm}+\rho g H$};
    \draw[blue!60!black,very thick] (0,\h) -- (\H,0);
  \end{scope}
  
\end{tikzpicture}


% TORRICELLI
\begin{tikzpicture}
  \def\W{1.6}       % tank width
  \def\H{3.0}       % height tank
  \def\h{0.94*\H}   % height water
  \def\t{0.06}      % hole size
  \def\ya{0.12*\h}  % lowest hole
  \def\yb{0.90*\h}  % highest hole
  \def\ym{{\ya+3*(\yb-\ya)/(\N-1)}} % indicated hole
  \def\N{6}         % number of holes
  
  % WATER
  \draw[vertical water,draw=none]
    (-\W,0) rectangle++ (\W,\h);
  \draw[mydarkblue] (-\W,\h) --++ (\W,0);
  \draw[double=watercol!90!black!90,mydarkblue,double distance=1.7,line width=0.15]
  \foreach \i [evaluate={\y=\ya+(\i-1)*(\yb-\ya)/(\N-1);}] in {1,...,\N}{ %;\v=1.2*sqrt(\h-\y)
      plot[samples=100,smooth,variable=\x,domain=0:2*sqrt(\y*(\h-\y))](\x,{\y-\x*\x/4/(\h-\y)})
  };
  \draw[dashed] (0,\h) -- (\h,0);
  \draw[dashed] (-0.05,\ym) --++ (-0.75*\W,0);
  \draw[width]
    (-0.5*\W,\h) -- (-0.5*\W,\ym)
    node[midway,fill=watercol!80,inner sep=1] {$h$};
  \draw[vvec] (0.05,\ym) --++ (0.45*\W,0) node[midway,left=2,above=-1] {$\vb{v}$}; %_0
  
  % CONTAINER
  \draw[thick]
    (-\W,\H) |-++ (\W,-\H)
    \foreach \i [evaluate={\y=\ya+(\i-1)*(\yb-\ya)/(\N-1)}] in {1,...,\N}{
      -- (0,\y-\t/2) (0,\y+\t/2)
    } -- (0,\H);
  
\end{tikzpicture}


% PRESSURE HEIGTH DIFFERENCE
\begin{tikzpicture}
  \def\L{4}          % distance pistons
  \def\Lx{0.60}      % left piston horizontal radius
  \def\Ly{0.10}      % left piston vertical radius
  \def\Rx{1.20}      % right piston horizontal radius
  \def\Ry{0.20}      % right piston vertical radius
  \def\H{3.0}        % height tank
  \def\d{0.28*\H}    % diameter connecting pipe
  \def\hL{0.86*\H}   % left height water
  \def\hR{0.74*\H}   % right height water
  \def\pt{0.05*\H}   % piston thickness
  \def\prx{0.040*\H} % piston pole radius
  \def\pry{0.006*\H} % piston pole radius
  \def\pLl{0.15*\H}  % left piston pole length
  \def\pRl{0.26*\H}  % right piston pole length
  \def\xL{0.30*\H}   % right piston displacement
  \def\xR{\xL*\Lx/\Rx} % left piston displacement
  \def\F{0.3*\H}     % force magnitude
  
  % WATER
  \draw[water,rounded corners=2]
    (-\Lx,\hL) |-++ (\L+\Lx+\Rx,-\hL) |-++ (-2*\Rx,\hR) |-++ %arc (360:180:{\Rx} and {\Ry}) --++
    (-\L+\Lx+\Rx,-\hR+\d) |- cycle; %(-2*\Lx,\hL-\t) -- arc (360:180:{\Lx} and {\Ly}) -- cycle;
  \draw[blue!30!black,dashed] (-\Lx,\hL-\pt-\xL) arc(180:360:{\Lx} and {\Ly});
  
  % PISTON
  \draw[metal]
    (-\Lx,\hL) --++ (0,-\pt) arc (180:360:{\Lx} and {\Ly}) --++ (0,\pt)
    (\L-\Rx,\hR) --++ (0,-\pt) arc (180:360:{\Rx} and {\Ry}) --++ (0,\pt)
    (0,\hL) ellipse ({\Lx} and {\Ly})
    (\L,\hR) ellipse ({\Rx} and {\Ry});
  \draw[metalcol!20!black,dashed,very thin]
    (\L+\Rx,\hR-\pt+\xR) arc(0:180:{\Rx} and {\Ry});
  \draw[metal]
    (-\prx,\hL+\pLl) --++ (0,-\pLl) arc (180:360:{\prx} and {\pry}) --++ (0,\pLl)
    (\L-\prx,\hR+\pRl) --++ (0,-\pRl) arc (180:360:{\prx} and {\pry}) --++ (0,\pRl)
    (0,\hL+\pLl) ellipse ({\prx} and {\pry})
    (\L,\hR+\pRl) ellipse ({\prx} and {\pry});
  \draw[metalcol!20!black,dashed,very thin]
    (\L-\Rx,\hR-\pt+\xR) arc(180:360:{\Rx} and {\Ry});
  
  % CONTAINER
  \draw[thick,rounded corners=2]
    (-\Lx,\H) |-++ (\L+\Lx+\Rx,-\H) --++ (0,\H)
    (\Lx,\H) |-++ (\L-\Lx-\Rx,-\H+\d) --++ (0,\H-\d);
  \draw[thick]
    (0,\H) ellipse ({\Lx} and {\Ly}) (\L,\H) ellipse ({\Rx} and {\Ry});
  
  % FORCES
  \draw[force] (0,\hL+\pLl+\F) --++ (0,-\F) node[pos=0.4,left=-1] {$F_1$};
  \draw[force] (\L,\hR+\pRl+0.02) --++ (0,\F) node[midway,above=3,right=-1] {$F_2$};
  
  % AXIS
  \draw[->,thick] (-\Lx-0.2*\Rx,0.9*\H) --++ (0,-0.52*\H); %node[left] {$x_1$};
  \draw[->,thick] (\L+1.2*\Rx,0.6*\H) --++ (0,0.40*\H); %node[right] {$x_2$};
  \tick{-\Lx-0.2*\Rx,\hL-\pt}{0} node[left=-1] {$0$};
  \tick{-\Lx-0.2*\Rx,\hL-\pt-\xL}{0} node[left=-1] {$x_1$};
  \tick{\L+1.2*\Rx,\hR-\pt}{180} node[right=-1] {$0$};
  \tick{\L+1.2*\Rx,{\hR-\pt+\xR}}{180} node[right=-1] {$x_2$};
  
\end{tikzpicture}


% PRESSURE TORRICELLI
\begin{tikzpicture}
  \def\Rx{1.0}
  \def\Ry{0.05*\Rx}
  \def\rx{0.18*\Rx}
  \def\ry{0.06*\rx}
  \def\H{1.0}
  \def\h{0.72*\H}   % water level height
  \def\th{2.7*\H}   % tube height
  \def\ty{0.95*\th} % tube level
  \def\td{0.6*\h}   % tube depth
  \def\N{14}
  
  % WATER + CONTAINER
  \draw[vertical water] %rounded corners=2
    (-\Rx,\h) --++ (0,-\h) arc(180:360:{\Rx} and {\Ry}) --++ (0,\h);
  \draw[water]
    (0,\h) ellipse ({\Rx} and {\Ry});
  \draw[thick] (0,\H) ellipse ({\Rx} and {\Ry});
  
  % TUBE
  \draw[vertical water]
    (-\rx,\h) |-++ (2*\rx,\ty) --++ (0,-\ty);
  \draw[water]
    (0,\h+\ty) ellipse ({\rx} and {\ry});
  \draw[thick,line cap=round]
    (-\rx,\h) --++ (0,\th) coordinate (T) arc(180:0:\rx) --++ (0,-\th);
  \draw[mydarkblue,line cap=round]
    (-1.09*\rx,\h-0.005) arc(180:360:{1.09*\rx} and 1.12*\ry);
  \foreach \i [evaluate={\y=1.12*\H+0.84*\th*\i/\N}] in {0,...,\N}{
    \draw[line cap=round] (\rx,\y) arc(0:-50:{\rx} and \ry);
  }
  \begin{scope}
    \clip (-\Rx,\h) |-++ (2*\Rx,-\h) --++ (0,\h) arc(360:180:{\Rx} and {\Ry}) -- cycle;
    \draw[thick,line cap=round]
      (-\rx,\h) --++ (0,-\td) (\rx,\h) --++ (0,-\td);
      %(-\rx,\h) --++ (0,-\td) arc(180:360:{\rx} and {\ry}) --++ (0,\td);
    \draw[vertical water,opacity=0.5]
      (-\Rx,\h) --++ (0,-\h) arc(180:360:{\Rx} and {\Ry}) --++ (0,\h);
  \end{scope}
  \draw[mydarkblue]
    (-\Rx,\h) arc(180:360:{\Rx} and {\Ry});
  \draw[<->] (0.6*\Rx,\h) --++ (0,\ty) node[midway,fill=white,inner sep=1] {$h$};
  \draw[very thin,line cap=round]
    (T)++(130:\rx) node[anchor=-19,inner sep=1] {$P=0$} to[out=-50,in=170]++ (-30:1.5*\rx);
  \node[above] at (-0.6*\Rx,\H) {$P_\mathrm{atm}$};
  
  % CONTAINER
  \draw[thick]
    (-\Rx,\H) --++ (0,-\H) arc(180:360:{\Rx} and {\Ry})
              --++ (0,\H) arc(360:180:{\Rx} and {\Ry}) -- cycle;
  
\end{tikzpicture}


% OPEN MANOMETER
\begin{tikzpicture}
  \def\W{0.8}       % pressure box height
  \def\H{0.7}       % pressure box height
  \def\Rx{0.55}     % tube bend radius horizontal
  \def\Ry{0.2*\Rx}  % tube bend radius vertical
  \def\rx{0.28*\Rx} % tube radius horizontal
  \def\ry{0.28*\Ry} % tube radius vertical
  \def\HL{1.3}      % tube height left
  \def\HR{2.2}      % stube height right
  \def\hL{0.40*\HL} % water level height left
  \def\hR{0.95*\HR} % water level height right
  %\def\th{2.7*\H}   % tube height
  %\def\ty{0.93*\th} % tube level
  \def\N{14}
  
  % WATER + CONTAINER
  \draw[water]
    (-\Rx,\hL) --++ (0,-\hL) arc(180:360:\Rx) --++ (0,\hR) --++ (2*\rx,0) --++
    (0,-\hR) arc(360:180:\Rx+2*\rx) --++ (0,\hL);
  \draw[water]
    (-\Rx-\rx,\hL) ellipse({\rx} and {\ry})
    (\Rx+\rx,\hR) ellipse({\rx} and {\ry});
  \draw[thick]
    (-\Rx,\HL) --++ (0,-\HL) arc(180:360:\Rx) --++ (0,\HR) coordinate (T) arc(180:0:\rx)
    --++ (0,-\HR) arc(360:180:\Rx+2*\rx) --++ (0,\HL);
  \draw[thick]
    (-\Rx-\rx,\HL) ellipse({\rx} and {\ry});
  \foreach \i [evaluate={\y=(\hL+\hR)/2+0.8*\HR*(\i-\N/2)/\N;}] in {0,...,\N}{
    \draw[line cap=round] (\Rx+2*\rx+0.007,\y) arc(0:-50:{\rx} and \ry);
  }
  %\draw[line cap=round,myred] (\Rx+2*\rx+0.007,{(\hL+\hR)/2}) arc(0:-70:{\rx} and \ry);
  \draw[line cap=round,myred] (-\Rx+0.007,\hL+\hR-\HR-\rx) arc(0:-70:{\rx} and \ry);
  \node at (-\W/2-4*\rx-\Rx,\HL+1.7*\rx) {$P_\mathrm{atm}$};
  \draw[very thin,line cap=round]
    (T)++(130:\rx) node[anchor=-19,inner sep=1] {$P=0$} to[out=-50,in=170]++ (-30:1.5*\rx);
  \draw[dashed] (-\Rx,\hL) --++ (1.3*\Rx,0) (\Rx,\hR) --++ (-1.3*\Rx,0);
  \draw[<->] (0,\hL) -- (0,\hR) node[midway,fill=white,inner sep=1] {$h$};
  
\end{tikzpicture}


% MANOMETER
\begin{tikzpicture}
  \def\W{0.8}       % pressure box height
  \def\H{0.7}       % pressure box height
  \def\Rx{0.55}     % tube bend radius horizontal
  \def\Ry{0.2*\Rx}  % tube bend radius vertical
  \def\rx{0.28*\Rx} % tube radius horizontal
  \def\ry{0.28*\Ry} % tube radius vertical
  \def\HL{1.3}      % tube height left
  \def\HR{2.2}      % stube height right
  \def\hL{0.40*\HL} % water level height left
  \def\hR{0.80*\HR} % water level height right
  %\def\th{2.7*\H}   % tube height
  %\def\ty{0.93*\th} % tube level
  \def\N{14}
  \draw[water]
    (-\Rx,\hL) --++ (0,-\hL) arc(180:360:\Rx) --++ (0,\hR) --++ (2*\rx,0) --++
    (0,-\hR) arc(360:180:\Rx+2*\rx) --++ (0,\hL);
  \draw[water]
    (-\Rx-\rx,\hL) ellipse({\rx} and {\ry})
    (\Rx+\rx,\hR) ellipse({\rx} and {\ry});
  \draw[thick]
    (-\Rx,\HL) --++ (0,-\HL) arc(180:360:\Rx) --++ (0,\HR) arc(180:0:{\rx} and \ry)
    --++ (0,-\HR) arc(360:180:\Rx+2*\rx) --++ (0,\HL)
    arc(0:90:\rx) --++ (-\rx,0) --++ (0,0.7*\rx-\H/2) -|++ (-\W,\H) -|++ (\W,0.7*\rx-\H/2)
    --++ (2*\rx,0) arc(90:0:2*\rx) -- cycle;
  \draw[thick]
    (\Rx+\rx,\HR) ellipse({\rx} and \ry);
  \foreach \i [evaluate={\y=(\hL+\hR)/2+0.8*\HR*(\i-\N/2)/\N;}] in {0,...,\N}{
    \draw[line cap=round] (\Rx+2*\rx+0.007,\y) arc(0:-50:{\rx} and \ry);
  }
  \draw[line cap=round,myred] (\Rx+2*\rx+0.007,{(\hL+\hR)/2}) arc(0:-70:{\rx} and \ry);
  \draw[line cap=round,myred] (-\Rx+0.007,{(\hL+\hR)/2}) arc(0:-70:{\rx} and \ry);
  \node at (-\W/2-4*\rx-\Rx,\HL+1.7*\rx) {$P$};
  \node[above=2] at (\Rx+\rx,\HR+\ry) {$P_\mathrm{atm}$};
  \draw[dashed] (-\Rx,\hL) --++ (1.3*\Rx,0) (\Rx,\hR) --++ (-1.3*\Rx,0);
  \draw[<->] (0,\hL) -- (0,\hR) node[midway,fill=white,inner sep=1] {$h$};
\end{tikzpicture}


% TURBULENCE - REYNOLDS
\begin{tikzpicture}
  \def\xmax{4.9}
  \def\ymax{2.9}
  \def\Nx{5}
  \def\Ny{4}
  \coordinate (M) at (0.95*\xmax*3.37/2/\Nx,0.9*\ymax*0.88/\Ny); % mount Everest
  \coordinate (S) at (0.95*\xmax*10.13/2/\Nx,0); % sea level
  
  % SKY + MOUNTAIN
  \fill[top color=blue!80!black!20,bottom color=blue!80!black!5]
    (0,0) rectangle (\xmax,0.9/\Ny*\ymax);
  \fill[top color=blue!50!black!50,bottom color=blue!80!black!20]
    (0,0.9/\Ny*\ymax) rectangle (\xmax,\ymax);
  \begin{scope}
    \clip (0.2*\xmax,0) --++ (0.07*\xmax,0.14*\ymax) --++ (0.02*\xmax,-0.03*\ymax) -- (M) -- (0.4*\xmax,0);
    \fill[white] (0.1*\xmax,0) rectangle (0.4*\xmax,0.5*\ymax);
    \fill[top color=white,bottom color=green!60!black!90,middle color=brown!80!black!80]
      (0.1*\xmax,0) rectangle (0.4*\xmax,0.1*\ymax);
  \end{scope}
  \draw[thin] (0.2*\xmax,0) --++ (0.07*\xmax,0.14*\ymax) --++ (0.02*\xmax,-0.03*\ymax) -- (M) -- (0.4*\xmax,0);
  
  % AXES
  \draw[->,very thick] (-0.05*\xmax,0) -- (1.08*\xmax,0) node[right=8,below left=10] {Pressure $P_\mathrm{atm}$ [hPa]};
  \draw[->,very thick] (0,-0.05*\xmax) -- (0,1.10*\ymax) node[below=8,above left=13,rotate=90] {Altitude $h$ [km]};
  
  % LINE
  \draw[mydarkblue,very thick]
    (0.02,0.95*\ymax) to[out=-90,in=150,looseness=0.8]
    (M) to[out=-30,in=178,looseness=0.8] (S);
  \fill[green!70!black] (M) circle(0.02*\ymax) node[green!50!black,below=1.7,left=0.8,scale=0.85] {Everest};
  
  % TICKS
  \foreach \i [evaluate={\y=0.9*\ymax*\i/\Ny; \h=int(10*\i)}] in {1,...,\Ny}{
    \tick{0,\y}{0} node[left=-1,scale=0.9] {\h};
  }
  \foreach \i [evaluate={\x=0.95*\xmax*\i/\Nx; \p=int(200*\i)}] in {1,...,\Nx}{
    \tick{\x,0}{90} node[below=-1,scale=0.9] {\p};
  }
  \draw[dashed]
    (0,0.9/\Ny*\ymax) --++ (\xmax,0)
    node[left=7,below left=-1] {stratosphere}
    node[left=7,above left=-1] {troposphere};
  \draw[dashed]
    (S) --++ (0,\ymax) % --++ (0,0.05*\ymax) (S)++(0,0.2*\ymax) --++ (0,0.8*\ymax)
    node[right=15,above left=-1,scale=0.9] {\SI{1013.25}{hPa}};
\end{tikzpicture}


\end{document}

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